Github seems to have no legit need for a user's phone number. Since there's not even a way to tell them to go pound sand, I'd say opting out of disclosing sensitive information they don't need by not signing in/up and equating their unreasonable demand with a ban is respectable.
I mean, obviously you disagree with them being generally reputable, but you must realize that’s not a broad opinion, and they are certainly better at preventing data breaches than the average company that stores phone numbers.
Sincerely though, I hope you get your GDPR request sorted.
Are you talking about Microsoft here? https://en.wikipedia.org/wiki/Microsoft#Controversies
Not mine and it sucks that this means I'm not welcome as FireFox contributor anymore unless I move countries just to register a monthly contract for a dedicated GitHub-accepted SIM card.
Once you trigger phone-number verification requirement your account is globally shadowbanned and support blocked pending SMS code verification. Aside from the privacy issue it's completely blocking people in the several countries (beyond the ones offially totally banned due to sanctions) to which GitHub won't even try to SMS/call.
Remember that registering a second account would be violating GitHub ToS.
Far less than these?
https://news.ycombinator.com/item?id=40592789
https://news.ycombinator.com/item?id=12305598
https://en.wikipedia.org/wiki/Criticism_of_Microsoft#Privacy...
This is unlikely.