About the one you are referring to, the letter i is in small letter and not in capital letter
Real: @t47inaugural.com
Fake: @t47lnaugural.com (with a lowercase “L” replacing “I”)
If real email is in capital letter, it will be harder to know the real one from the fake one because I (i) is harder to differentiate from l (L).
This is the format hackers used to scam multinational companies off their mailbox, they simply hack the mail, clone the name of mail that wants to do business with the other companies and hide the real negotiator away from the business discussion. This format is very popular and it's hard to detect too because the difference in letter and alphabet is hidden a little bit.
To avoid being the prey on the Internet you'll need to be as smart as those scammers sometimes even smarter to make it tough to be their victims, it doesn't only end with being knowledgeable cause lots of people who claim to have knowledge still got scammed, take the recent case of Trumps inaugural donation scam for an instance.
The Donor who got scammed was an intelligent person, he might even attended the best school abroad but he wasn't smart or careful enough to notice the format the scammer used to steal the donations. But I believe that after that particular case lots of companies and donors would start being extremely careful even though I'm pretty sure that some would still fall for it.