What's with being farsighted AND nearsighted? This sucks!

So, also being aged and decrepet my vision has gone craptastic as well. I am astigmatic and presbyopic but I detest bifocals. [mainly because I lay on my side a lot thanks to joint issues, and you really can’t watch tv on your side with bifocals. I have the older style with about a third of the lens as the reading part not the little barely fingernail of reading part. I need more than a fingernail to focus on the speedometer and gauges in car. I prefer to be safe when driving thanks.]

So I found these interesting glasses online, but they say not for astigmatics. Why? Why would adjustable lenses not be for astigmatics?