These are the companies you want to be at IMHO. Provided the compensation is adequate, slow and stable > fast and pivot-y.
Absolutely...not.
Slow does not mean stable. Slow means the floor is rotting out from under you constantly.
Being prudent about when and where to upgrade is a very active, intentional process that the typical company simply don't have the stomach or skill for.
That platform got SMP in 1964.
Not chasing shiny is important but generally when tech debt builds up this high, life is generally hell in terms of outages, unable to accomplish basic tasks and dealing with a bunch of people who have NIH syndrome.