Tim Culpan from Bloomberg notes that Mastodon has grown as a result of Elon Musk's tumultuous time at Twitter.
But he also implies that Mastodon languished until this tumult. It's true Mastodon's been around since 2016.
However, ActivityPub wasn't officially introduced by the W3C until 2018. Development has been ongoing.
Growth has been steady, though it spiked recently.
Often for open source projects, maturity takes time.
https://mobile.twitter.com/business/status/1627836863212929026
@atomicpoet @fediversenews I think Mastodon has exceeded Twitter in every regard but raw user count.