Mac mini (2018) running poorly after upgrading from Ventura to Sequoia

To expand a bit on Owl-53's recommendation:

You have a lot of old stuff, some of it installed over a decade ago.

Starting clean will get rid of all that cruft.

You should make sure to have an up to date Time Machine backup before anything else.

In recent mac models, starting fresh is very easy:

1) System Settings->General->Transfer or Reset:

choose "Erase all content and settings".

This will leave only the OS, and is very quick.

2) When asked, choose to migrate content from "another mac, disk or Time Machine backup".

NOW comes the crucial point: Check ONLY the user accounts, not applications, settings or other files.

After this step you have your content (documents, pictures, music, etc) as well as your personal preferences.

3) Install the applications that you do use, from the App Store or their developers' sites.

To start with delete these files & restart…

   ~/Library/LaunchAgents/com.adobe.ARM.***.plist

   /Library/LaunchAgents/com.adobe.GC.AGM.plis

   /Library/LaunchDaemons/com.adobe.agsservice.plist

   ~/Library/LaunchAgents/com.adobe.GC.Invoker-1.0.plist

   /Library/LaunchAgents/com.adobe.GC.Invoker-1.0.plist

   /Library/LaunchAgents/com.softraid.SoftRAIDMonitor.plist

tilde indicates the home folder.

Your best bet ( IMHO ) would to run the Etrecheck Application and Post the Full Report

There is obviously something ( Process or Processes ) running that is causing this issue

This is a Diagnostic Tool that makes no changes to the computer.

It makes a coherent and readable inventory of both the Hardware and Software used on the computer 

The application is free or paid for added features. 

The Report will Not Reveal Any Personal Information. 

Sequoia runs better on our 2018 Mac mini, 512GB, w/20GB of RAM, than Ventura and Sonoma.

Instead of going back and forth for days playing 20 questions.

Download and run the free version of EtreCheckPro, from > https://etrecheck.com/en/index.html

Then post back here with your Report, as per > How to use the Add Text Feature When Post… - Apple Community

Quick review of the report

Start Over from Scratch - full stop

Do Not use Setup Asset or Migration for a Recent TM Backup.

Install only the absolutely Required Third Party Applications

We may get some clues if you can provide an etrecheck report…

https://etrecheck.com/en/index.htm

Try resetting the SMC.

Reset the SMC of your Mac - Apple Support

If I my rejoin this lively issue

To add to both what @Luis Sequeira1 and @den.thed have mentioned

A Clean Installation from scratch and Stop at that point - full stop

I know I suggested reinstalling your Hird Party Softwares

I would like to retract that statement

Running a Pristine and Virginal Installation of Sequoia 15.5 without any Baggage at all

Would be akin to an almost Out of the Box experience

It would also be a very good indicator if these ongoing issues maybe or may not be related to a Hardware Issue

FYI. No doubt if one were have the machine Services By Apple.

They may insist on doing the same Before that would investigate if there was indeed a Hardware issue

Just saying, in friendly terms

Quit often but not always

Etrecheck may reveal applications running or installed on the computer that the Owner is not comfortable being exposed for others to see

As mentioned, sometimes but not always

Owl-53 makes a good point.

Your 2018 Mac mini Runtime: 7:00

Performance: Below Average

My 2018 Mac mini Runtime: 3.21

Performance: Excellent

The main reason for your poor performance, is that you have tons of third-party Apps, Unsigned Apps, Extensions and other junk installed on your 2018 Mac mini.

Your 2018 Mac mini.

My 2018 Mac mini.

FWIW I also have MacFanControl and CarbonCopyCloner, but not much else in the way Launched, User Login Items or Extensions installed on my 2018 Mac mini.

Owl-53 wrote:

It would also be a very good indicator if these ongoing issues maybe or may not be related to a Hardware Issue

I did not see a problem with Hardware per say, at least not with the OPs Apple Storage Drive.

The OPs 1T Apple SSD Write/Read speeds are slightly better than my 512GB Apple SSD Write/Read speeds, which is normal for the larger SSD.

Sorry for the delay in posting. I had to stop and help my wife with her dumb Android Phone. 😝

Thank you 👍 or the astute observations visa vie SSD drive of OP

Have an ancient Honor with Android 4 or something or other for the powder-room reading times lol

No SIM just wifi

Otherwise, iPhone 15 Pro for really work

Yea' I do not need to have the latest and greatest. In fact, I just upgraded my beloved iPhone 8 to an iPhone 14 thru my Consumer Cellular plan. At this point, I think I've pretty much convinced the wife to replace the Andorid with an iPhone sometime this year.

l008com wrote:

Honestly I feel like that program is mostly just nonsense.

I would say what you "feel" has nothing to do with it. It's the most recommended diagnostic program here on ASC for a reason.