That would mean you would be indefinitely supporting and sending traffic to X. Why not tell your million followers "I will only be posting on Bluesky now - please check out my profile there [link]" and dump X? If you're worried about your numbers dropping moving to the other platform, then your "followers" probably don't mean much or weren't that interested in what you have to say anyway (so what's the point other than a score)? Maybe I'm just doing the old man shaking his fist at the sky routine.