The potential monetization being the donations to give them a living wage? What exactly is the criticism about, that they shouldn’t get a living wage through donations and should rather make the platform paid or ruin it with ads?

Why do so many people get off on attacking the idea of FOSS, much of the software that is running our everyday lives is supported through FOSS (and lots of them are also being donated to so that the devs can afford to put food on their tables).

There are also many devs (on Lemmy as well) that contribute a lot without being paid, simply because they like the project, want to make it better, and want to learn by doing.