I've never used Google Voice so I cannot say about that. Where I'm at you can buy a cheap phone for like $20 and it comes with a prepaid SIM that never expires. I have about 10 of those on a drawer on my desk LOL, it goes well with the hacker vibe B). Funny thing is I don't have them labeled, so when I need it I have to turn on all of them to see which one gets an SMS.

For email, my domain provider handles email for me as well, I have a Google Workspace account and first thing I do when I set up an email is to link it there so I have a single Inbox for everything. (Although my real Inbox is the Spam folder, where a lot of genuine emails land now).

Google Voice only works in the US so not an option for most people.

A lot of services block VoIP numbers (including Google Voice), especially if two factor or some sort of verification is involved.