The reason I am asking is that I see volunteering time for extremely wealthy big corporations as foolish.
At very least developers should get together and lobby that if big corporations use open source software, they should be paying royalties to contributors.
That said, if you look at volunteering time, it is much better to do it for charities that often struggle getting competent IT people, but of course it is not as glamourous.
Which is also worth something.
Chromium is open source, in my opinion, because Google can brag about open source, it has all the right buzzwords. But also gives them free R&D and labour.
I think given the size and wealth of Google, this is entirely inappropriate and people shouldn't be contributing to it, because it will only encourage this parasitic and exploitative behaviour.
I'd argue it's one of the least "parasitic" corporate OSS project.
There certainly are OSS projects out there where the majority of work is done by volunteers and where companies profit from their labor. This isn't really one of them, at least not in the way you are describing it.
Applying one "truth" to the entire world generally means that you're simplifying things to such a degree that they become meaningless or even ridiculous parodies of themselves.
I feel like that this might be what you are doing here.
So you would rather have chromium be closed source, or for people to fix the bug but hoard the patches? Do you hate the idea of google benefiting from your work so much that you're willing screw over yourself (in the form of having to maintain the bugfixes yourself) and others (because they don't get the bugfixes) in the process? Are you also against contributing improvements to other OSS projects (eg. linux kernel) because corporations might benefit from it and "gives them free R&D and labour"?