Built in SD Card Reader on OS Monterey 12.5 not working

Sorry, guess the wording was confusing my old mind and thought the Card Reader was a USB Type

Sometimes a SMC Reset may bring it back to life

Reset the SMC of your Mac

It will depending on the Card Reader and just how exactly the Card Reader is attached to the computer.

Much like USB Hubs have be problematic in Monterey - some work and some do not. It is dependent upon the Chip Set inside the the Card Reader

Has the user attempted connecting the same Card Reader, the exact same way, to another Apple Computer running an older version of macOS ? Does it work there ?

The only way to be sure is to go back to 12.4.

Make sure to send feedback to apple to make sure they are aware:

Product Feedback - Apple

If you have it, you might also want to call Apple Care.

You are welcome 👍 and thank you too 🇨🇦

Do come back to the Apple Support Communities ( ASC )  in the future, if / or when additional questions may arise