If your point is more than everything online is virtual anyway, then you're missing the point.

Your email being tied to your online identity doesn't mean it's part of your sense of self or personality. It means it's ties to multiple online services that identify you partly by using it. If you change or lose your email, you lose those log-ins or, at least, it's a pain to change them all.

Many places now use a phone number as an identifier instead of an email or as an alternative. Again, because it's unique to you and unlikely to change. However, that makes you easier to track and susceptible to losing it being a loss of things beyond your phone number. This may include access to things like bank accounts or personal photos or friends contact details.