What is the process EscrowSecurityAlert in Activity Monitor?
Yes, it's part of macOS &amp; has been since perhaps Mavericks.
Wikipedia lists it in List of macOS components but provides no description -
The iPhone Wiki gives a brief description

This application works with the iCloud Keychain servers. It manages the password uploads and anything that keychain tools does.

By definition an escrow service is one who acts as a middle-man in a complex or expensive process. It is often used when buying/selling a house. The escrow company holds both the deeds and the money until all parties have completed the legal requirements to transfer the property, preventing either one from 'running off with the money'.
In computing terms it is an arbitrator between two not-necessarily-yet-trusted 'clients'. It prevents any data from one leaking to the other until full trust is established. In effect, it doesn't let anything 'run off with the money'.
This is, in effect, a less mind-numbing version of your last link &amp; quote.