Is Matt Mullenweg defending WordPress or sabotaging it?

As an open source creator, I can understand Matt's position to some extent and the frustration behind seeing some competitor profiting from his work. He is clearly eccentric. The part about him asking WP Engine for revenue-sharing in exchange for changing words in his speech made me chuckle. What I don't understand is why he cares so much. He is probably one of the wealthiest OSS people of all time so it seems petty in that context.

I think when you're rich you'd rather give charity to the needy than to other rich guys.

I suppose. Maybe he should be spearheading some movement or lobby to help give special treatment for open source creators.

If he is just suing that company, it's really about himself and his interests. He is right to notice the moral incongruence but he can't expect other people to support him in his personal quest to get justice just for himself.

What he sees as gross abuse is just day-to-day reality for the vast majority of open source developers. Many of whom struggle to get by and struggle to find jobs.

Companies which refuse to even extend OSS devs a job interview are making out like bandits on top of their work while simultaneously using VC funds to raise entry barriers and ad costs so that the OSS devs cannot even compete in their own industry which they contributed to. The typical skilled OSS dev ends up with no jobs, no funding, no opportunities.

OSS devs can't even afford legal representation so legal precedents are meaningless to them.

So in what way is he giving charity to other rich guys?

Or do you mean that any OSS dev is giving charity to people making money using that software?