Licenses that have legal compatibility problems with other licenses are problematic. In fact, that's one of the reasons copyleft licenses are problematic: legal incompatibility with many other licenses. In that respect, AL2 is as problematic as some copyleft licenses.
It also comes with some weird bookkeeping issues, like having to mark changed files in ambiguous circumstances, and requirements for how a file with a particular name (NOTICE) must legally be treated. These kinds of things can add to the burdens involved in building derived works, maintaining modified forks, or borrowing code.
It also comes with some weird bookkeeping issues, like having to mark changed files in ambiguous circumstances, and requirements for how a file with a particular name (NOTICE) must legally be treated. These kinds of things can add to the burdens involved in building derived works, maintaining modified forks, or borrowing code.