There’s still no good way for me to write an open source web application and have its users bear the cost of running it. This is a major regression from open source desktop software, and IMO is the reason open source web applications haven’t taken off more.
I think we need something like micro payments. Take lichess for example it's the biggest open source chess website completely ad free and runs by donations. If you divide the total monthly costs to run the servers by the number of games and you get a tiny fraction of a dollar cent. I don't remember the exact number, but it has been in the order of 1k chess games equals 1$. If you could charge 0.1 cent per game, then…
This revenue model has turned out to be quite profitable in gaming and creates an experience where most people can use the software for free but a long tail of users spend lots of money to have icons next to their name or elsewhere on the site.
For chess you can imagine how this might work, for other software it is not always as clear.