[jiveturkey]

No hesitation: yes. Intel Macs will be supported for a long time to come, easily for the next 6 years you cite. And you won't have to deal with 1st gen ARM bugs. And you can use it now, not 1 or more years from now.

iMac is not upgradeable however. don't kid yourself.

> macOS will certainly not be supported for 6+ years (assuming a similar timeline as during the last transition).

Don't understand this at all. macOS will be supported forever. Did you miss a word?