Nope. The devs make a living out of it. They work on Lemmy full time. They are sponsored by NLnet and are paid for every feature they implement

Compleatly forgot to answer your other quesntion:

Yes the main income is donations. The difference is that you don't need to pay if you can't afford it and people who donate are generally paying more on average. The huge difference is that everyone has access to everything without paying.

Imagine what would happen if you would have to pay to use Wikipedia: nobody would use it. The content is made by users and if they would have made it a paid encyclopedia it wouldn't have any users.

Not a problem. Also FOSS orgs pay their devs as well. Off the top of my head OS developers with a large userbase often pay their devs through donations to foundations that fund the project. Often donors are companies as well, but it gives a developer the option to get paid without working for a massive company.

(I suppose indirectly they do, but that's a whole different ball of wax)

I don't understand. I reread back to the top comment and went down the chain. They made a rhetorical question about how devs of software being paid. Someone clarified the definition of Foss. Then there was a an inquiry about how someone could make a living with FOSS software and another commenter claiming millions do it (which a majority are these exact devs I pointed out).

I simply gave the list, that's all.