There seems to be pervasive opinion among FOSS enthusiasts that the software being free and volunteer made is kind of get out of jail card for not only criticism, but often simply just feedback.

I deeply appreciate that FOSS exists. But - subjective feeling - in general it always had certain reputation for jankiness and user unfriendliness. Sniping down feedback "because the software is free" certainly contributes to that perception. If I have a choice between free, volunteer made software that's unreliable or doesn't even work for some of my use cases, and a commercial, but non-free product, I will be pragmatic about it and choose the latter.

Criticism can be constructive. For understaffed teams, patches are even better.