My understanding is that, by volume, most people using Linux "in anger" (whose needs mostly dictate the direction of Linux development) aren't the SREs maintaining living systems for years at a time; rather, they're the DevOps people with constant streams of greenfield projects, involving half-baked third-party components, that in turn need all sorts of random bleeding-edge dependencies.
A working system calls for a conservative viewpoint. I'm only looking to introduce change if my needs aren't being met.