The content format is basically identical. I think claiming that it’s not a rival based on technical implementation details isn’t giving it enough credit.

You can also think about alternatives like Truth Social and Parler essentially cloning the Twitter content format, aren’t they also Twitter rivals? Couldn’t they be seen as different “instances” of Twitter with different moderation standards given that their functionality is basically identical?

In other words, the conversation should move away from “How does this work on a technical level?” and more toward “what value does this have for me?”

The truth is that Mastodon, regardless of instancing, holds the same value proposition as Twitter. It’s a legitimate alternative.

IIRC, truth social is a custom mastodon instance.