I think it's a great idea regardless of practicality / implementation which I think is generally understood to be largely a matter of time, money and hardware. I feel like you write it up so the idea gets out there or you can pitch it to someone if the opportunity arises.

Oh and also I second the fast.ai suggestion, part 2 is 100% focused on implementing stable diffusion from scratch in the python standard library and it's amazing all around. The course is still actively coming out but the first few lessons are freely available already and the rest sounds like it will be made freely available soon.