In the early days of the internet it was a standard that people had different accounts on different sites and there wasn't any federation. We're doing it right now - my hacker news account doesn't work on mastodon or on reddit.

Perhaps part of the reason we don't do that any more is that signup is so high friction? It used to be just username, password, confirm password, captcha, submit. But now it's username, password, confirm password, email, phone number, captcha, submit, go to phone, open email app, wait for slow loading, refresh, wait for slow refresh, click email, see long link, click link, "this must be opened on the device you signed up with", back, retype 100 random characters on the computer with perfect accuracy, "email verified", next step, go to phone, open SMS app, wait for slow loading, no new SMS, back to computer, "send code again (wait 60 seconds)", wait 60 seconds, click it, go to phone, finally get a 6-digit code, back to computer, type it in, submit.

Signing up for things is a massive chore now. Because they want so much personal identification data, that they don't actually need for the function because they never send an email or an SMS.

And if you're signing up on the same device you're checking your email and SMS on, it's straight up impossible because every time you switch to the email app, it unloads the browser app and forgets its state so the verification is invalid. You have to keep trying 6-7 times and hope maybe one time you'll do it quick enough that the browser will stay resident in memory.

I actually have at least two phone apps that are social-adjacent that do signup secretly in the background. You just install the app, and it generates a random identifier and uses that as your account ID. Nothing is visible to the user. In the settings is an import/export option for device migration. If you want signups, this is how to get them.