Yeah, I'm not sure I see the benefit in this. I think the last thing we need is to create more obstructions to people creating and promoting modules, and, while I agree that we need a base level of conventions that a module should follow, this one feels a bit arbitrary to me, and I have a high level of confidence that a convention will naturally evolve.
As a parallel, I look at the way Composer packages have evolved. It's pretty much standard fare that packages are named [vendor-name]/silverstripe-[module-name]. It's not always the case, but enough so that it's workable. That came about naturally, and we didn't have to impose it. I think the less we impose, the more people will want to contribute.