Flattr is the kind of idea that sounds great, that people love talking about - if only they could make a small donation to every website they liked - but that doesn't work because people are fundamentally too selfish. This is why ads are the only viable business model for a kind of "ephemeral website" - something you visit only briefly, derive some short knowledge or pleasure from until you follow a link somewhere el…
I see a lot of people either proposing using paypal, patreon or ko-fi to receive donations. How did flattr differ from these services?
That's a model that helps avoid subscription fatigue. Put $10 or $20 or $100 into a pool, and at the end of the month you know you'll spend exactly that much, no matter how many sites you flattr.
I would love to have seen that model succeed.