It's in the nature of developers to care about API design, which is really what this is about. Would you want someone to design an API for your software product that does so as haphazardly as the PHP standard library was designed? Probably not. It's only natural that people want to discuss why it's bad and how it could be fixed. I would be more concerned if you were a developer and didn't care about these kind of issues.

I would like to think that in any sane project they would choose one of the namespaces and stick with them. Moreover, I think that as you deprecated the older namespaces, this problem would go away.

You could make the exact same argument with removing register_globals: half the project using it, while half the project using the superglobals. Clearly there'd be some pain, but I don't think it would be as bad as you're trying to make it sound.

I'm not really sure I follow the logic that if someone has an issue with the state of a programming language then they shouldn't be developing. How does that make any sense?