I mean he's been running version 20 for years already, what's changed to make it now suddenly insecure?

Everything is insecure, the question is has anyone found the vulnerability in it yet

I look at it as “The risk of running unmaintained code on an old interpreter version is difficult to quantify and therefore it is low cost and effort to require it run on a maintained, recent version.” Developers will argue their time is too valuable to require such code be updated to run on recent interpreter versions, and I’ll argue it’s cheaper than chasing successful exploits and any footholds established. Dev Vs Ops, a tale as old as time.

Perhaps having had to run down potential exposure across a large enterprise from the recent npm supply chain attack has made me a bit more paranoid lately around supply chain and cicd security. But, I get paid to be paranoid, so it is what it is. Run your own runners I suppose? Hard to complain when someone else is running the infrastructure for you (and you’re not paying enterprise prices). Supply chain and hosted/multi tenant execution code security is just fundamentally hard and fraught with peril. Ongoing deprecations to keep up with current state are therefore unavoidable.