> At the mercy of all the big providers that could one day just decide to turn our account off without a reason.

This had me genuinely concerned when a lot of the superfuous account bans were happening on Twitter and Facebook around the 2020 election cycle. Retweeting a joke could knock you off, and I'd been using Twitter as a 2FA for many/most sites where it was offered at the time.

Now, I'm much more inclined to choose email/password options. I've also been using a wildcard domain for most new things. Ex: site@mydomain, etc for every site, store, etc I use.