[ConcernedCitizen]

In regards to what exactly do you refer?

Just thinking about whether it makes the se more believable if a more commonly used email domain is used. Or do they just not care about that?

They 100% do care if you're using a radical hosting for email. But you also shouldn't be using your own Gmail because that is one way to get your email burned. Use a throwaway that looks legit (and of which you have taken over); it should be fine. Typically, your own email would be fine but you're better off buying an account from a vendor that sells full accounts including two- or multi-factor authentication (2FA). If you don't know where to buy these accounts with multi-factor authentication (MFA) (2FA), I can point you to a few people:

1) Me! I sell full accounts if you're interested. All legit, including recovery and they are verified. Primarily Gmail.
2) Sure you can find others in the Market that are selling as well.