What I expected to happen was...:
Launching the new MCL should allow me to use Minecraft regardless of whether my Minecraft account is tied to the same Microsoft account as my Windows login or Microsoft Store app uses.

What actually happened was...:
After switching to the new MCL, I now semi-regularly receive an error stating "Minecraft Launcher is currently not available in your account. Make sure you are signed in to the Store and try again. Here's the error code, in case you need it: 0x803F8001".  This error does not occur every time, and it also doesn't appear to prevent me from launching Java edition.  However it does every so often ask me to confirm the Microsoft account that I wish to have the MCL logged in by, requiring me to log it in again.  While this error is intermittent, I also notice a big red bar message is always visible in the launcher which reads "You are not signed in to Microsoft Store with the account you are currently using in the Launcher.  Click here to review your accounts.".  Clicking this link launches the Microsoft Store app and shows me a login dialog box to state that I'm logged in with my Windows account, not the one that I purchased Minecraft with.  This all reads to me, the user, as though the MCL thinks all of this is a big problem, as though I'm doing something wrong.  I'm not, I just have multiple accounts in use, so why should this be of concern to the MCL.  Surely I'm not the only user with this scenario?

Steps to Reproduce:
1. Log into Windows with a Microsoft account that is different to the one that Minecraft was purchased under.
2. Launch the new MCL.
3. [Intermittently] Receive error dialog stating error above with code 0x803F8001.

4. Receive an error stating that my MCL account is different to my Microsoft Store account.