I ask inspired by experiences with Google. Google/YouTube, for as long as I can remember, always had a strange habit of assuming absolutely anyone even near to you is you. Back when I had my first YouTube account (which was also back when I was in a completely different part of the world), for the last few years of having it, it had my sister’s channel listed under “alternate accounts” and it wouldn’t even ask me for the password to log into her account, I could simply click over to it like it was nothing (led to a lot of sister rivalry moments). Of note, on a less severe scale, something akin to this mindset is also credited to leading me to witnessing a documented and verifiable triple banning of cherished accounts, how lovely.
So yeah, my first curious hypothetical question I have of the year. How common/normal would this stance be on the net, with something like 2FA where it could mean the difference between data and makeshift DNA (secondary question, does it actually work as well as touted years ago)?
Some sites and apps tie your account to the a phone number (messengers are especially annoying in this regard, you still can’t use Signal without a phone number). Many others accept a bunch of accounts with the same phone number, but there’s usually a limit to make it harder for spam farms to enter a platform.
I don’t believe getting phone banned is common, except for phone oriented platforms like messengers.
As for your Google thing: that’s not the result of your phone number matching, that’s an account thing. Your sister’s YouTube channel is attached to your Google account (probably as a “branded account”). This could’ve happened back during the Google+ days when YouTube did all kinds of weird shit. It’s highly likely that your account and your sister’s YouTube account will get banned together if you can access hers without logging out and entering her password instead. If this is the case, you can transfer a YouTube account to your sister’s Google account, though. Watch out to follow official Google guides om this if you decide to start the process because scammers are known to steal accounts through this transfer process.
Google is particularly nasty when it comes to certain bans. If your account is used to commit sufficient (Google Play) fraud, it becomes infectious. Your personal account will be banned, your professional account will be banned, your employer’s accounts will be flagged, and if you get a new job and don’t create new Google accounts, your new company Google account and employers’ accounts will be flagged as well. This type of ban is normally reserved for ad fraudsters and click farms, it doesn’t happen accidentally, but if it happens to you, you MUST use separate devices, accounts, and preferably internet connections, or the company you work for may run into problems. This approach works well in preventing fraudsters from starting “new” companies when they’re caught, but it’s aggressive as hell.