How to deauthorize device on Apple Music

Apple has the instructions below in the support page Authorize or deauthorize your computer for iTunes Store purchases - Apple Support

If you need to deauthorize a computer that you don't have access to

To deauthorize a computer that you don't have access to, you have to deauthorize all of your computers. Then authorize each computer that you have again. You can deauthorize all computers only once a year.

1. Open the Apple Music app or Apple TV app.
2. Choose Account > Account Settings.
3. Sign in with your Apple ID and password. Forgot your Apple ID?
4. At the top of your Account Information page, go to the Apple ID Summary section.
5. Next to Computer Authorizations, click Deauthorize All.
6. Authorize each computer that you use again.

That doesn't work because one of my devices that I want to keep is old. Apple iTunes says it's not compatible. I just want to deactivate the computers that are fried. Surely, there is a way to do that.

The deauthorize all command only relates to computers, not other devices. Once all past authorizations are invalidated you will be able to authorize up to five computers once more. An authorized computer can sync any unprotected media, and protected media from up to five different accounts, to an unlimited number of Apple devices. A maximum of 10 computers and devices, no more than 5 of which can be computers, can be associated with your Apple ID for downloading past purchases and streaming Apple Music content.

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See also Authorization vs. association - Apple Community. You may have some now unused associated devices that you want to remove.

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