
It’s difficult to do when anything starting to become widely useful or good invariably gets fractured (forked) because different people need different features/capabilities.
It’s the double-edged sword of “open”.
I don’t point this out to criticize, just to acknowledge the challenge that exists, for which I don’t have an answer.
How much people are willing to pay for software is a bit of a reflection of the utility of it (of course, marketing is a part too, look at games).
I’ve seen some OSS apps with business sponsors who use the app in some way. One that comes to mind is Möbius, a Syncthing client on iOS. The business sponsor uses Syncthing as part of their business with their clients. Syncthing lacked a good iOS client, and apparently this business really needed one, so they developed one, and sell it on the App Store (with the approval of the ST devs).
Another issue is the difficulty of donating to projects. Each one is a different process, so I have to figure it out and keep track of who/what I’m donating to. Having 2 or 3 systems that could funnel donations to projects would be useful (those could be OSS projects too, with a minimal cost per transaction to subsidize the system maintenance and credit clearing house costs).





Syncthing-Fork has been out for years and has more options too