Does anybody care about Wordpress, though? The only times I ever hear about it are when somebody's discovered another few dozen security holes. It seems to be more of an experiment in poor design than a serious project.
If his beliefs are correct, it is illegal to distribute proprietary software that only runs on Linux.
If his beliefs were correct, nobody would touch anything GPL'ed with somebody else's penis. His beliefs are either posturing or a sincere misunderstanding of copyright.
If his beliefs are correct, it is illegal to distribute proprietary software that only runs on Linux.