And with unified memory, you need to share with the GPU, which will have at least 2x framebuffers at full screen resolution and bit depth, as well as any/all required texture memory, shaders, etc. Likely won't even have anywhere near 8GB for the system to use.
No, it's not Bob. What's your devs team default?
Depends what you're doing with your computer. I'm editing something right now on an M1 Mac Mini with 8GB of RAM (with Final Cut Pro).
Would I run Docker on here? No way. But a lot of professional tools run just fine with 8GB.