Surprisingly, it looks like Bluesky is outperforming Mastodon:

https://trends.google.com/trends/explore?date=today+5-y&q=bl...

https://www.similarweb.com/website/bsky.app/#traffic

If this holds true, it is a big win for interface over functionality and under-the-hood-technology.

Mastodon is based on a pretty good protocol (ActivityPub) and has many instances. But the usability is terrible. Bluesky on the other hand only has a single implementation and instance, and I find the protocol (The AT protocol) harder to grok. But the interface of the one instance is way better than any Mastodon instance I have seen.