Of course GitLab can do something about it. It happened, as their tweet says, because they changed vendor. So it sounds like they may be able to work around it by changing their hosting choices.

Also, this may come as a shock to you, but when a law is sufficiently unjust, there can come a time to disobey the law. In this case, disobeying the law would not directly risk anyone's safety, lowering the barrier somewhat.