Github has the same policy, and it deterred me from using MFA for a long time, and when I finally did, I added a large number of alternatives, including the not-so-secure SMS.
I think the fear of being temporarily unable to access your account is already a major reason why people don't use MFA. Turning the threat into a permanent loss will make people even more reluctant to do it.
Dealing with some of the backup methods (e.g. off-site copies of backup codes) is tedious, and I wouldn't be willing to do it for less important sites. If I had 2FA on Gitlab, I'd probably turn it off now. (Actually, just saw they don't have an option to add a phone number - I'd definitely turn it off.)
I may have misread the announcement, but it sounds like upgrading to a paid account recovers (npi) the ability to recover your account.
Or rather, at least as straightforward as the process is meant to be for existing paid-up customers, as per TFA.
I wish conpanies offered this as a feature, in the sense I'm much more worried about someone SEing their way into my account rather than me losing access to all my MFA methods and backup codes or whatever.