This is not directly related to freedom, as you can see from there being two completely opposed ways to deal with the issue.
No, it's not about being picky with your users, but about what is best for the project long term. It's well known that Linus thinks that keeping a reputation of not breaking things (knowingly and arbitrarily) is good for the Kernel. The glibc people probably think that not allowing clearly buggy code to tie their hands is best.
Different options, and yet none is necessarily wrong, because they apply to different stuff.