Labradoodles were bred to solve a problem-- blind people with dog allergies (or, I imagine, partners with dog allergies). Poodles are hypoallergenic, and I guess fairly trainable, but not quite enough to be service dogs for the blind, and they need grooming that gets expensive. Labs are the fave breed for service dogs for the blind (Seeing-Eye is a trademarked term, and I’m avoiding it on purpose), since GSDs fell out of favor for being so inbred.
If you want a Labradoodle for a service dog you have to request one be trained for you (or, at least that’s where the matter stood the last time I had a conversation about it with someone who would know, and that was pre-pandemic, so the situation may have changed, as have so many).
No one was trying to create a breed. Every year, a few Labradoodles were requested, so a few litters were bred-- being a dog for the blind is demanding, and not all puppies make the cut, so out of each litter, you might get one.
There was no vision of getting the to breed true.
But, the idea of part-Poodle breeds captured people’s imaginations. Maybe partly because the hypo-allergenic idea worked, but I suspect it was mostly novelty, and then the other people who jumped in with other crosses they wanted to see just for the cuteness factor. Let’s call it the Frankenstein factor.
I’m sure it will wear thin at some point.
It’s also my understanding that Labradoodles were not explosively successful as service dogs, because not enough puppies from each litter managed to make the service-for-the-blind cut, but they have worked out well as other kinds of service dogs where the training is not as demanding.