> Pay for what? It's not about making money.

For servers that run Mastodon.

> But that sort of total exodus would mean a lot of additional people contributing ideas and code to the Fediverse, not just servers, but by making it easier to run your own instance.

Most users aren’t interested in contributing anything to the platform. Social media platforms popularity lays in simplicity. No one wants to run anything, just use service without any hassle.

> there are upwards of a million people using it right now.

Compare that to 200m+ users of Twitter sending 500m+ messages daily. I bet Mastdon can handle this without a sweat.