While I applaud compensating FOSS developers, there’s a devil in the details: all software stands on the shoulders of many giants. The nature of software, and software users, means that most money is going to go to front-end developers, regardless of effort. They, in turn, would have to rigorously re-distribute most of that money to the developers of the great many many libraries and frameworks that their software depends on. I would argue that it is practically impossible for this trickle-down to happen fairly, which would result in developers of deep, indirect dependencies used by everyone being ignored. Throw a shitty, low-effort GUI on restic, and you’d end up with all the donations. If you’re ethical, you’d give 99 cents for every dollar to the restic devs; how likely is that? An added wrinkle is that people are really bad about estimating the relative worth of their efforts; even if everyone in the stack is ethical, how do you estimate the relative value of your effort against the effort of the database binding library you use? How much of your donations do you give to each developer of the 40 libraries you directly import?
Another issue I personally have is that compensation invites obligation. It breaks the itch-scratching foundation of FOSS.
Finally, I think introducing money into FOSS is a virus that ultimately destroys the only functioning communism in the world. It changes developer behavior, or at least introduces perverse incentives, in undesireable ways. I’d rather end-users contribute in whatever way they can: well-written bug reports, PRs that fix spelling in docs, wiki “how-to” contributions, code contributions. From each, according to ability. That’s what keeps FOSS running, and that’s the spirit of FOSS.
Now, I’m fully in favor of for-profit companies funding and supporting projects. They’re making money off FOSS, and should roll that down. All of the same trickle-down issues apply, and certainly it introduces the same perverse incentives, but greed should have a cost, and all for-profit companies are by definition engines of greed.