I can't speak for anyone else, but I don't mind at all when an open source project switches licenses or whatever. They gave away the fruit of their labor, but I am not entitled to any more of it.
What does bother me is when the projects pivot to claiming that users now have a moral obligation to financially support the project. There is a kind of dishonesty in this move.
It's not that a successful project "should be free", it's that its success depended on it being free. If they had said all along that they'd eventually ask users to pay, that would be honest... but then they wouldn't have seen much of that adoption in the first place.
> I can't speak for anyone else, but I don't mind at all when an open source project switches licenses or whatever. They gave away the fruit of their labor, but I am not entitled to any more of it
It only bothers me when they try to claim their new license is open source or use misleading language when it isn't. Which seems to be what 90% companies doing that do.
People can do whatever they want with their intellectual property as long as they aren't lying about it.
In my case, I never intended on my open source project becoming popular, it just did and I had to either abandon it or make it my job. I'm not sure where that falls in your judgement.
I suspect this is also the case for PHP though.