Running IDEA, a Java backend, a nodejs frontend, a secondary nodejs frontend and a browser with dev tools open has caused my computer to hit 32GiB of RAM usage easily. I didn't decide the tech stack, unfortunately, but this has become a real problem.
Personally I think 8GiB should be more than enough for any normal end user though the Electronification is taking a real toll these days. However, this is the M2 Pro, labeled for professionals, and professionals generally need more resources. Capping the machine at 32GiB means I can't even comfortably run my current stack without swapping. I can only imagine what this will do do professional video/photo editing.