I'm not familiar with these specific cases but I do think that many popular open source authors are extremely rigid and uncompromising. And yes, personal attack

I'm not familiar with these specific cases but I do think that many popular open source authors are extremely rigid and uncompromising. And yes, personal attacks against prospective contributors is a very harmful thing for the project. There are nicer ways to reject PRs and proposals that don't push away contributors. Also, I'm a firm believer that very talented people can make very silly mistakes sometimes so you can't assume that someone has no value for your project just because their work or idea was disappointing on a single occasion. When open source project leaders show aggression towards well-meaning people, it's a blatant display of arrogance and egomania.