Did you ever get a full fix to this?

Have you tried contacting apple support? Again, this is probably a problem best directed towards them.

This is again, probably something more for YouTube feedback, and not for the developer forums. The developer forums are where developers ask questions to one another, not necessarily give feedback on non apple made apps. I recommend you direct this to YouTube support or go through feedback assistant.

No one knows if the next MacBook Pro/MacBook Air is going to have Face ID. They wouldn't tell us this here, and something like this is probably directed towards Feedback Assistant rather than the Developer Forums.

This probably isn't a question for the developer forums. You should probably contact Apple Support in regards to this.

Firebase is an easy to implement option. Just note that some of the things with firebase are out of date. For example, if you use firebase and follow their process, you'll put the code for Firebase.configure() inside AppDelegate.swift. Last time I used firebase that was slightly out of date. Alternatively, other database vendors exist. You could use CloudKit which is native to Apple, or use something like Vapor and set it up yourself. There's a load of different database vendors you could use for a backend. However, Firebase or CloudKit are probably the two easiest to use in terms of extensibility in swift.

And this is why developer forums should filter certain topics lol, this is not the place to ask these type of questions, none of us have a say in that. that's saying a lot too, since iOS 13 supports pretty much most modern iOS devices