That's my feeling too. Tools like this are trying to squeeze into the space between "straightforward configuration easily maintained in static files" and "comp

That's my feeling too. Tools like this are trying to squeeze into the space between "straightforward configuration easily maintained in static files" and "complicated state management better served by real code in a real programming language". And that's a real hole for some applications, but it's a small hole. Basically forcing everyone to learn new tooling (Pkl here, but lots of json/yaml middleware nonsense fits the bill too) just to deal with what really isn't that big of a problem seems like a bad trade.