MacOS Monterey 12.6 has slowed down my computer

I had the similar issue on my iMac 2020 (see my thread). I tried a lot different way, even do the re-install (with erase the hard drive). Finally solve the problem by resetting the SMC :

• Turn off your Mac and remove the power cord from the back of the device
• Wait for at least 15 to 20 seconds and plug the power cable back in
• Finally, wait for another 5 seconds and power on your Mac as you usually would.

Hope this can help to solve your situation.

evstein wrote:

3 TB Fusion Drive

SMART status is verified on Disk Utility.

This may be part of the problem. The Fusion drive is almost entirely a mechanical drive, with a very small SSD attached. Most of the data are stored on the mechanical sectors. 12.6 has APFS and is VERY SLOW on mechanical drives. See this

https://bombich.com/blog/2019/09/12/analysis-apfs-enumeration-performance-on-rotational-hard-drives

There are two ways around this. One is to have an authorized Apple service provider replace the internal drive with an SSD. This is something a qualified technician needs to do, most people should not be undertaking this themselves. Alternatively, some have recommended setting up an external bootable SSD to run from instead of the internal drive.

Before doing anything, it might be good to download DriveDX to check the physical health of your drive. SMART is fine but DriveDX shows all the different health parameters and you should run the LONG DriveDX diagnostic test. Also, I suggest that you download Etrecheck and run it with full disk access, post the output here with the Additional text button below. There could be some other problem.

What type of internal drive do you have? Is is a SSD, or a Fusions drive (or mechanical HDD)?