I think freemium models are a good solution. Look at sites like Music streaming, mail services like tutanota. I seems fair to me to get a basic, somehow limited services for free and if you want more, you have to pay for that.
Agree, however, I had Nebula via curiosity stream. I found however that Nebula lacked quantity. I has some decent quality for not enough for that price. I also means yet another wallet service. It would IMO better to have a service like peertube with paid instances/clients.
You also have MeWe. This is a freemium social media without ads. It was to silent for me but there are alternatives.