Yes. Because it’s funny and I don’t have any other account.
I don't see the humour.
I can’t help you.
didn't ask
Technically (or, at least, historically), they should have used the indefinite pronoun "one" i.e. "...because their defense systems seem overly sensitive to one's email address". But I imagine that would've got more comments than using you/your.
No, using “your” in such a context is a manipulation tactic.