I keep my 2019 iMac at Mojave for the same reason, it will never see a newer OS.
As for my 16" M1 Max MBP, I recently updated from 12.2.1 to 12.3.1 to see if it would resolve the notorious "
iCloud Drive needs to finish updating before being turned off." issue that seems to popup with various OS incarnations (it did resolve).
As for further OS updates, I've generally brought my previous machines up to a certain "satisfaction level" and then ignore any further OS packages, my interest in, um, "new" UI features is minimal and I keep up, mainly, with security patches...this will eventually be the case with the MBP.
Being an "Old Dog" here who still runs Snow Leopard on a 2010 and 2011 iMac for many tasks it's disappointing to see how Mr. Job's OSX-nee-MacOS has turned into such bloatware over the past decade, my 2019 i9 iMac is, in fact, slower at certain tasks than those older machines because of all that behind-the-scenes continually-running processes load! Ha! Methinks there would be a major purging of OS programmers and a slimmer and more efficient OS today of he were still at the helm.
Vote: "depends on specific needs"