Do we need to run malware and/or anti virus software on Big Sur on M1 Mac mini?

No. 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.  

There are no known viruses, i.e. self propagating, for Macs.  There are, however, adware and malware which require the user to install although unwittingly most of the time thru sneaky links, etc.   

Anti Virus developers try to group all these types as viruses into their ad campaigns of fear.  They do a poor job of the detecting and isolating the adware and malware.  Since there are no viruses these apps use up a lot of system resources searching for what is non-existent and adversely affect system and app performance.

There is one app, Malwarebytes, which was developed by a long time contributor to these forums and a highly respected member of the computer security community, that is desshoigned solely to seek out adware and known malware and remove it.  The free version is more than adequate for most users.  

You shouldn't rely on third-party software to protect your computer. Most antiviruses will only slow down your system and interfere with the built-in protection provided by apple. Try to avoid apps such as Norton, Clean my mac, Mackeeper, and the like. No, they're not all scams, viruses, or junk, but they are practically useless. These companies prey on fear and give you little in return. Stay away from VPN's, antiviruses, cleaners, optimizers, and similar software.

I guess if it does that, then it will also catch the 1,000,000+ Windows viral junk too.

Protecting Windows users is not your responsibility. Windows malware will not affect your mac.

Guard dog or no guard dog for M1?

Regardless of whether or not you need an antivirus, you shouldn't rely on the M1 chip to protect you, as proven by the recent "silver sparrow" attack. These attacks will only grow in number.

The weak link in a mac's security is not the lack of antivirus software, it is the human that uses it.

No software, hardware, or operating system can ever offer complete security to its users. You must protect yourself from threats to your cybersecurity.

That being said, Malwarebytes is a free tool that can be used to scan for malware that you have already installed. It is the only security software you should ever install or use. If you are interested, take a look at this guide:

Joseph Coates wrote:

Do we need to run malware and/or anti virus software on Big Sur on M1 Mac mini?

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No.

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