My Mac Mini is running too slow

It would be beneficial to post the EtreCheck report here so we can review it.

To check the health of the drive, run DriveDx and post the complete text here using the "Additional Text" icon which looks like a piece of paper. If you have a Fusion Drive setup, then post the complete reports for both the Hard Drive and SSD.

Disconnect all external devices in case one of them is causing a problem (except for Display, keyboard & mouse of course, but make sure nothing is connected to any ports on the Display).

This is a BIG part of yout issues. YOur hard drive, already a slow model to start with, is transferring data at HALF its nominal speed:

Performance:

System Load: 2.75 (1 min ago) 2.55 (5 min ago) 2.88 (15 min ago)

Nominal I/O usage: 1.37 MB/s

File system: 54.76 seconds

Write speed: 38 MB/s ⚠️

Read speed: 32 MB/s ⚠️

Those speeds could simprove when you get rid of the useless "protection" you were sold. It interferes with elegant self-maintenance routines you paid Apple to build into the macOS.

You also have components of CleanMyMac running:

[Loaded] LaunchAtLoginHelper (MacPaw Inc. - installed 2023-04-28)

Modern Login Item

It has been documetned here as slower drive perforamance among other offienses.

Almost all client-side VPNs are sold by fear, not effectiveness. Your ISP has server-side protection so putting extra stuff on your Mac simply degrades performance.

There is some evidence that multiple ad blockers cause slowdowns. Find the one you love best and show the rest the exit.

Uninstall Norton, restart & do another etrecheck report.

Jarzoirmur Said:

"Mini running too slow..: Is there any solution? The unit is a late 2014 build - see below: Online connection fine - 500 mps up/down - but when the unit has to download mail or open apps, beach balls show up for 3 - 5 minutes. Genius Bar staff told me, after looking, that they couldn't figure it out[...]"

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Thank you for the screenshot.

Troubleshooting Lagging Mac:

A. Try Safe Mode:

In Safe Mode, login items do not run, and corrupt system files(i.e. caches) are intentionally reset as a way to fix issues

1. Boot: in to Safe Mode: [Hold Down: shift key upon boot].
2. Log in: as same user
3. Wait: 30 seconds
4. Restart; your Mac
5. Log in: as same user

B. See if your Hard drive is Failing:

What to Try:

• Verify your Drive: Repair your Disk in Disk Utility - Apple Support
• Go Here: If your Mac Starts Up to an Apple Logo or Progress Bar - Apple Support
• Perform the following in Recovery Mode:

1. Boot: into Recovery Mode. Go Here:  How to Use Safe Mode on your Mac- Apple Support
2. Select: Disk Utility
3. Select: the Drive
4. Click: First Aid button

C. Remove Login Items:

While in Safe Mode, remove all of your Login Items, and then restart the Mac.  Go Here: Change Users & Groups Login Items Preferences on Mac - Apple Support

D. RAM Consumption being the Culprit::

As for the beachball, it is telling you that an application or file or sorts is at work. Likely. this app is consuming lost of RAM. So, view the Activity Monitor, seeing what is consuming the most of it, and close whatever it may be. More on Activity Monitor: Activity Monitor User Guide - Apple Support.  See my reply to this post: News Streaming Sites Consuming Lots of RAM ( >4GB) - User Tip

I don't see the DriveDx report here. Please include the EtreCheck report as well.

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