I never buy anything first gen and I'll wait about 3-4 years after the apple silicon matures.
I generally agree with you and I would be hesitant to buy a 1st gen ARM mac. I also avoid major updates until the first revision comes.
However, listen to this... I bought the 1st gen 15" Macbook Pro. It was one of the first Macs with an Intel CPU. Aside from a battery recall, it was awesome. And my mom still uses it today. My little bro got the bigger 17" at the same time. It also sits on a side table and is used occasionally. I think Apple built them better back then, though. I would be less willing to take the same risk today.
So on one hand, I wouldn't put off buying a new computer if I needed one, just to wait for the newest thing. But on the other hand, if I needed a new mac immediately, and the 1st gen was the current offering, then I would probably get it. But I would probably get some Applecare just in case. I definitely wouldn't wait 4 years though.