Is CleanMyMacX a good software to use?

If you search here in the Community (use the search facility at the head of the page) the message is very clear - avoid this software.

This thread from a few years ago is typical. The OP found that a new Mac was very slow, but much improved after CleanMyMac was removed.

The best action you can take is apply each macOS update as Apple releases it.

Never install any app that claims to "tune up", "speed up" or "clean up" your Mac. These apps exist for one reason: to separate the unwary and inexperienced user from their hard-earned money. At best they do very little, at worst, they can damage your OS installation and cause far more problems than they "solve".

Concur with previous posting.

Any Third Party Applications that will interfere with the normal operation of the OS, alter, modify, remove or delete or attempt to do so is an invitation for disaster and comprising the Operating System

It may require a Reinstallation of the OS in-order to replace any modified, altered, removed or corrupted elements of the OS this software has inflicted on this computer 

Any of the below should be removed as per Developers Instructions 

This will include CleanMyMac

Uninstall CleanMyMac per their directions , then run etrecheck again to see what chaff it left...

On CMM…

iMac running slow, several apps unrespons… - Apple Community

https://discussions.apple.com/thread/251442443?answerId=252814053022#252814053022

https://discussions.apple.com/thread/251464557?answerId=252841819022#252841819022

https://discussions.apple.com/thread/251889446?answerId=253629452022#253629452022