Communities can be full of hypocrites who can't stop talking how diverse and inclusive they are and how everyone should feel welcome and safe, and at the same time either engage or be consciously oblivious to backstabbing inside — as long as the appearances are kept.
Communities can be poisoned by newcomers who would like to reform them from the ground up not a week after joining.
Communities can contain influential members with whom you are assumed to be always agreeing, and you can be expelled for not being thrilled with their ideas. And you are expected to be aware of everything dear leaders write or shoot videos about.
The outsiders may like to cherry-pick some behavior they label "problematic" from more prominent community members and label everyone as the carrier of such behavior.
Some communities would like to drag you in and have you commit to them if you only want to contribute a little something.
I have a gas stove at home. I'm by no means a member of some kind of gas stove users community (does it even exist?). I don't share tips on using your gas stove better, and I don't spend time bickering about advantages of gas stoves over electric ones.
I sometimes do drive-by pull requests to some projects which I use myself and which proved to be useful enough. Doesn't mean I "belong" or am "bound" to those projects in any shape or form.