There are some big brain companies who will block you if their name appears in the email address. Like Discord. You can create an account, with [email protected]. But a seconde later you will get an email that your account got band.
They know their way around IT security! /s
What you say is often true, but in the case of Discord, at least in my case, you are wrong. My Discord email address is [email protected], and I am still receiving emails from them.