I bought an M1 Max with 64gb of ram at release. I'm still not sure what will get me to replace it other than it simply breaking. Maybe an M5 will finally make me want to buy something new. I'm debating getting a cheaper Air and maybe a base Ultra now that I do most of my heavy work at a desk.
My M1 still holds right up! It is the smallest RAM model, and even that is not the end of things.