Slow Mac

Are there any AntiVirus, Disk Cleaner, Optimizers, Defrag, VPNs etc installed which should be removed as per Developers Instructions. They are useless, unneeded, cause havoc and interfere with the normal operation of the OS. The Built-in Security of Big Sur is all that is required.

Generally, the AppCleaner from Apple Apps Store are Trusted but I personally Never use any Uninstaller. If the Developer of an Application does not allow Drag and Drop to Trash or does not provide a Trusted method to remove the Application - I keep miles / KM away from them.

As for Slowness - what age is the machine. The expectations for some of the Older MBA dating to 2013 comes into play

Id say a factory reset and a upgrade to teh newest OS your system can handle is your best bet.