Incredibly slow boot time

There is no reason to ever install or run any 3rd party "cleaning", "optimizing", "speed-up", anti-virus, VPN or security apps on your Mac.  This user tip describes what you need to know and do in order to protect your Mac: Effective defenses against malware and other threats - Apple Community   

That being said you've installed a very intrusive, resource hogging and totally unnecessary bit of software, Intego software. It is very intrusive, installs many file throughout the system and run in the background. Uninstall it according to the developer's instructions. Then You can check to see if you've removed all of the supporting files by downloading and running Find Any File to search for any files with the application's name  and the developer's name in the file name.  For the Intego software you'd do the following search(es): 

1 - Name contains intego

2 - Name contains virusbarrier

3 - Name contains contentbarrier

4 - Name contains netbarrier

Any files that are found can be dragged from the search results window to the Desktop or Trash bin in the Dock for deletion.

FAF can search areas that Spotlight can't like invisible folders, system folders and packages.  

Rerun Etrecheck and verify that all intego files have been removed.

Another app that is not needed is Flash. Adobe is dropping it from support this month and most all websites have migrated over to HTML5 as a replacement. Again, uninstall according to the developer's instructions.

There is no reason to ever install or run any 3rd party "cleaning", "optimizing", "speed-up", anti-virus, VPN or security apps on your Mac.  This user tip describes what you need to know and do in order to protect your Mac: Effective defenses against malware and other threats - Apple Community   

You've installed some very unnecessary software: Intego software

020-11-29 VirusBarrier

2020-11-29 NetBarrier

Uninstall all of the Intego software according to the developers' instructions. Then you can check to see if you've removed all of the supporting files by downloading and running Find Any File to search for any files with the application's name  and the developer's name in the file name.  For Intego software you'd do the following search(es): 

1 - Name contains intego

2 - Name contains netbarrier

3 - Name contains virusbarrier

Any files that are found can be dragged from the search results window to the Desktop or Trash bin in the Dock for deletion.

FAF can search areas that Spotlight can't like invisible folders, system folders and packages.  

Rerun Etrecheck but this time with Full Disk Access setup for Etrecheck:

IMPORTANT:

Before running Etrecheck assign Full Disk Access to Etrecheck in the Etrecheck's Privacy preference pane so that it can get additional information from the Console and log files for the report:

Also click and read the About info to further permit full disk access.

You still have NetBarrier files installed.

System Extensions:

[Not Loaded] NetBarrier Extension - version 10.9.14 (INTEGO - 2020-11-19)

Application: - version ( - )

Remove the extension and recheck the performance. If that doesn't help remove all items from the System/Users & Groups/Login Items preference pane and check performance. If improved add them back one at a time rechecking as you go.

As systems evolve older apps can become less compatible with them. I'd remove those files from the Login Items section and check to see if there's any improvement If there is add them back one at a time to see which one causes the problem.

Please post the full Etrecheck report by copying it

and pasting it into your reply with the Additional Text button:

There may be items in the report that will catch our eye as potential problems.