I think what you're calling "elder devs" is actually the "intermediate" devs. They're not junior in any sense if they're capable/allowed to create these huge balls of mud we're referring to. And the elders normally have seen way too much to fall into that trap... and definitely don't quit often like you're describing at all (my experience is that the younger you are, the more often you change jobs - which is good for you as it's been shown this is the best way to get a good paycheck, but bad for employers, of course). They're tired of that constant churn and have had more than enough time to find a place where they're comfortable. The OP is likely talking about those as well, but from the perspective of someone who probably is truly senior and has been doing this at least since the 90's... basically, they're talking about the devs who know just enough to be dangerous (some will enter this stage from around 3 years of experience to 10, others may stay there from 5y to 20y - so it's difficult to group them together in a neat group) just like you're doing, but to you, they look senior as well.

It's Dunning-Kruger at work here.