So if they see closed source source as something not cool why they allow to close their source code?

Of course, strong copyleft licenses sometimes can hindering development for example GPL and CDDL license conflict don’t allow adding ZFS support to Linux Kernel. But it will not help with development when corpos are more taking than giving to project. Just look where’s Linux and where’s BSD - you can see how GPL hinder that development.

And why they see GPL license unacceptable in commercial use? For me unacceptable is to close source code, no matter if it’s for commercial use or not. For me open source is alternative for that shitty closed source commercial software. If I’ll try to make my own open-source commercial product based on BSD license it would be impossible. Competitor with more money for marketing will just take and close my source code, add few improvements then sell it as own product. Why I would like to risk that?

In the place of 1000 richest people we will get just new 1000 richest people in that case.