Oh they don't - you can sign-up without one, and iirc, Twitter doesn't indicate anywhere that one is needed. But all new accounts just happen to exhibit suspici

Oh they don't - you can sign-up without one, and iirc, Twitter doesn't indicate anywhere that one is needed. But all new accounts just happen to exhibit suspicious activity and are blocked until submitting a phone number. This is all mere coincidence, and certainly not an effort by Twitter to conceal how much personal information they want for an account.