I’ve maneuvered it so the launcher works, but when I use Modrinth, it still doesn’t work
I have had this exact same problem, I’ve played the game two days ago, and it is asking for my purchase of Java edition again although I already purchased it, oddly though, Bedrock Edition is still purchased and playable. Seeing as we both raised this issue today, I doubt this is a coincidence.
You have to use Xbox to press play, then reopen the launcher, and then Minecraft works again, but only directly from the launcher