Some good news. I updated my MacBook Pro (Intel) from Big Sur 11.6 to Monterey 12.0.1 tonight. After the 12.6GB download, I started installation. The install window said it would take 56 minutes, it actually took 14 minutes. Then it rebooted and was done in about 10 minutes. I only saw one Sophos entity in the top ten entries in Activity Monitor during the entire process, it was eighth from the top, and was there for a split second.
EAP Endpoint 10.3.0 seems to be a winner.
ibid
[edited by: Brian1941 at 2:04 AM (GMT -7) on 31 Oct 2021]