Yes, you want some old farts in the village.
The young and healthy can work the fields, but for the older and weaker folks there will be plenty to do that requires less brute strength. My simple garden this year involved a surprising amount of food processing at harvest time to convert the vegetables to something long lasting, this is even more true for subsistence farming. That’s just one example.
Well, that’s easy to do if you disregard all counter-evidence. Children living past five are upsetting your thesis? Ignore 'em!
You’re probably right. Of course, there would be very few of them in LudditeLand™ (The Unhappiest Land on Earth) thanks to deaths in childbirth and accidents in the fields and workshops and attacks from neighbouring villages, so the drain on resources probably wouldn’t be too bad. You could probably afford to have one or two crones per village.
And I’m the first to mention Dies the Fire? Y’all are really falling down on the job! 
While I totally agree that being without vaccines will cause a major upsurge in currently preventable diseases, I disagree that our current knowledge of the germ theory of disease will have little effect on our ability to reduce the effect of these diseases. It’s true that in the past, this knowledge didn’t help all that much (as in the case of polio), but our knowledge is much more advanced and widespread at this point. I’d imagine that if there was an outbreak of, say mumps, we’d be much more willing to use measures such as strict quarantines than we were in the past. The quarantines would be stricter and people directly taking care of the patient would also be more willing and able to use proper techniques within the quarantined area. Also, we’d probably be able to spread and disseminate knowledge about recognizing and treating these diseases more effectively than we’ve been able to in the past. So, yes, we’d go back to huge mortality (and disability) from these diseases, but maybe it wouldn’t be quite as bad as it has been in the past.
As far as old people, childcare, etc.: I can speak to how these things were frequently organized among plantation slaves in the antebellum American South. Nursing mothers did indeed take their infants into the field when possible. This was no longer feasible when they were toddlers. Elderly slaves and older children looked after younger children (where possible). At the same time, these elderly slaves and any children who were able did various types of more sedentary work. Sometimes, slaves who were “no longer useful” were sent off to (presumably) die, but most slaveowners didn’t do this because it caused the other slaves to rebel. (And remember–most slave rebellion wasn’t of the armed-uprising variety. But slaves would often engage in work slowdowns and such.)
I saw Szlater’s comment on preview–actually, the village could support more than a couple of old crones. They come in real handy. There is a lot of tedious handwork to do in pre-industrial societies. And somebody’s gotta spread those old wives’ tales, right? 
But as a practical matter, natural attrition will take care of most of the surplus old people.
Thanks for posting that. Looks like it jibes with one of my pet theories–that the maximum human lifespan has remained virtually unchanged over our recorded history. It’s just that more and more humans are getting closer to the maximum with reasonable health and quality of life.
I think that for the most part, Greens are trying to save modern society, not destroy it. Certain technologies are worth saving (health care, for example) and others are not (the car culture, is one example).
And to answer one question, while I don’t know who invented eyeglasses, Ben Franklin invented bifocals. Hearing aids, on the other hand, are truly modern.
In the 19th century they did quarantine strictly for diseases like diptheria. In other words, there was a period of time where we did have “modern” knowledge of certain medical facts but no treatment or vaccine. It wasn’t until the vaccine that all those little kids stopped dying of diptheria, regardless of quarantine.
ETA - and nobody mentioned Dies the Fire because it’s a sucky book. 
How? Can’t use telephones or the internet - them’s the tools of the Devil!
Water would be boiled more often. Battlefield surgery would be improved. The value of proper urban sanitation methods would be appreciated.
This would all help to some degree.
But crystals and metal spires are holy, so radio is A-OK. (When living in a theocracy, make your technology a ritual and your equipment religious icons. Besides, once you know how it can be difficult to not create an AM receiver.)
Transmitters, though… SATAN!
Health care is dependent upon cheap and easy car travel. Nothing else fast enough, ubiquitous* enough, and able to carry enough weight.
*(That is, it doesn’t depend on rails or timetables.)
Diphtheria.
It’s a pet peeve. 
No it’s not.
If you’re living in smaller communities you can provide healthcare on foot or by horse. If you’re living in the Australian outback, you need a plane. If you’re living in central London the doctors could make house-calls by Tube (or you could visit the doctor by Tube), and horse-drawn carriages could serve as ambulances.
It’s entirely dependant on the way your society is designed.
It ith?
Anyway, could central London get on without ambulances (and for that matter, police cars and fire trucks)?
I mentioned horse-drawn ambulances in the post above. Horse-drawn fire-engines existed before the internal-combustion engine, and I could see that working again (if need be), and the same for police vehicles.
And I wondered why Firefox didn’t think it was a word. Sorry.
Look, while the peasants and artisans are forbidden to use engines, surely the servants of Gaia will be permitted to use such things in their holy work. The peasants cannot be trusted with such things, but surely the village headmaster would only use his biodiesel powered Humvee in the service of Mother Earth.
What’s the comparative population density of central London now and central London in the age of dobbins, say 1900?
More to the point, is anything resembling a modern city even possible without mundane technologies like vehicles (personal or mass-transit) or electricity? How many “self-sustaining villages”, as described in the OP, would it take to hold the population of modern London?
We may have had the germ theory of disease, but the knowledge was nowhere near as sophisticated or widespread. If we were to start quarantining now, we’d be able to do it more effectively than they did then.
Many many people would still die. It would just be fewer than before.
Of course it’s a sucky book. But mentioning it seems to be de rigeur in any thread tangentially related to the subject. 
No. You can’t drag a stroke victim to a hospital across the village quickly enough to prevent death even if the hospital is miraculously stocked with modern equipment, partially because you can’t carry an ambulance’s worth of supplies with you and partially because carrying a person is a lousy way to move them if you are at all similar in weight and bulk. Horses (presumably pulling a wagon, assuming wheels aren’t outlawed) are an improvement but they are still more weather-sensitive than cars.
Comparing cars to planes is comparing chalk to cheese.
Back when emergency response meant being the absolute first to say there’s nothing we can do.
And some societies aren’t designed to allow victims of strokes or heart attacks to survive.
I think the Greens need to be a lot more honest about the real cost of their anti-technology bias. Learning about the dependencies between seemingly unrelated technologies is the first step.