I don't think that's true for all users, and maybe not even most. I'm not even sure that the people for whom it is true are key to other people's desire to use social media.
OTOH, persistence is key to social media where transssctionality is key to email, so losing a social media handle has a bigger impact on a social media user per se than does losing an email addresses to an email user.
No. That's true only for some users. Also tools like Mastodon are implementing multiple accounts / account migration.
Then why did you write this sentence and not "ActivityPub is like email"?
Mastodon would be like Hotmail, right?
Edit: meant to say Twitter and not Mastodon, to get the point across.
You would lose all subscribers, likes, comments etc.
Then you would have to find a way to prove to 'your' old friends that jbb67@someotherodomain.com is the same person as the person that formerly was 'jbb67@mastodon.social'. And have some of them follow you again etc.
The same process as if you changed from Twitter to Facebook.
At least you would have choices of who to trust on Mastodon, or if you trust no one then run your own instance.
based on my experience on fedi, i think you are exaggerating the fragility of the connections you make on social media. clicking "follow" isn't a lot of effort and people will do it when they recognize your voice coming from a new source.
Having your own domain name represents YOUR identity/persona on the web - nay, overall internet in fact. The focus here is on the portion AFTER the @ symbol. Yes, unfortunately for now, owning your own domain - for the purposes of interacting with other instances and people via these federation-type of technologies - also involves the overhead of hosting your own mastodon, gnu social, pleroma, ActivityPub server, etc. But in the future, it could be that the underlying mechanisms could be made much easier and cheaper both to use and to switch/jump...and for the most part you only need to hold onto your own domain name...and can switch to different underlying mechanisms/technology/providers/whatever...but the top-level identity is preserved as you cross to other instances, etc. Within the indieweb community - a community that supports efforts like ActivityPub, etc. - owning your own domain is usually the first step...because it represents the formal establishment of YOUR identity. An identity that you control, and where your friends/followers can always know and follow. I imagine in the future if more people adopt the practice of obtaining and sticking to using ONLY their domain name as an identifier, much of this will be easier and some it simply a moot point.