I'm experiencing the same Issue as the original Reporter.
The old Launcher prompted me to install the new Launcher from the Microsoft Store which I did.
I then removed the old Launcher.
Upon trying to play with my friends I was faced with the same Broken Screen (1.PNG).
Somehow Minecraft/Microsoft seems to have forgotten that I already own Minecraft for several years... and wants me to buy it again? just for the new launcher experience...?
In that case maybe Anthony Spinelli could reopen the Ticket?
Since I'm not the original reporter I don't seem to have that ability... and there seems really no point in opening yet another duplicate (most likely the reason they use such a bot in the first place)