We've actually witnessed that people _are_ willing to pay for streaming services like Spotify and Netflix after a long time of illegal torrents. How can we spread this sentiment towards services like email and chat too?
I remember vaguely getting convinced by a friend, "you just payed [200,300,idk]€ for that new phone, can't pay one euro for this one app?"
We can't, because those two things are in direct opposition. Piracy was less convenient and offered fewer features that people wanted, so they moved to platforms that were more convenient. The current giants (Gmail, Facebook, WhatsApp...) are more convenient than their alternatives (generic email, Mastodon, Signal...) and so the pressure is not to move, but in fact to stay.
In general, the pressure is always decentralised->centralised, which is exactly what torrents->Netflix was. Even if we had infinite funds to offer people distributed services for free forever, we would still need to make them more convenient than their current centralised ones - if on top of not being more convenient, we also want to charge them, I see no reason why the average person would ever want to switch.
Maybe there's some space for a freemium model (IIRC one of the questions asked during the Facebook hearing was whether they could add a paid ad-free option) but so far that hasn't happened.
I guess Matrix is doing this, but unfortunately, the way history has played out, centralized IM had first mover advantage by a huge margin and that's what people are used to now - that a messenger is an application on your phone that you can only use to contact other users of that same application.
