Mastodon has been around since 2016 and has 804k MAU.

The platform has 57 third party apps.

The platform is decentralized and has community ran servers.

Are you asking about "people" or "nerds"? People prefer Bluesky due to its simplicity and momentum. There are more popular outlets using it. If you're assuming that People would prefer the complexity of the Fediverse and instances, if you think People know what a decentralized community run server is, you're a "nerd" (for lack of a better term, I'm sorry).

The battle has always been the same: Windows v. Apple, Android v. iOS, SMS Twitter v. App Twitter. Some people prefer flexibility and investing time in making things work the way they want (Nerds). Some people want an out of the box product that's well designed and efficient (People).

Fifty Seven Third Party Apps is not a selling point - that's called anxiety inducing fragmentation. Some people want to walk down the grocery store aisle and choose between 57 options for toilet paper and some people just want "good", "better", "best". The reality is that most people just want to be told what to do. They have too much shit going on in their lives to care about "decentralization".

Mastodon will never challenge well financed closed or semi-open platforms. As it's designed, it's apparent it never intended to. It will continue to grow at a slow rate as an alternative. Hopefully, the fediverse is realized and you can choose to host your own server and gain access to other social platforms.

The reality is that this stuff costs money. In the near future, you'll have the same three choices with social media as we do with other services: ad-subsidized, subscription, self-hosted. Anything with ads is going to have an algorithm. Anything with a subscription is going to have a board of directors. Selfhosting comes with a steep learning curve.