I had different emails for all those accounts. On some reddit info page it says it uses "current" Ip address and device screen resolution info to link accounts to each other.
I think that might be a lie. They have to be keeping at least 5 years of data . Maybe even older.
I also change my IP address all the time.
They must be tracking some other identifying info. Like device sign in name (Google account/windows login) or something.
I don't know but I was very surprised they found all my accounts so easily and banned them all.