At least with web apps, that tends to be the “Redux” style more than the “React” style causing that. Basically, lazy state management (and I mean this pathologically rather than in terms of Haskell’s ‘lazy’). The laziness comes from the business side of things, squeezing more productivity out of engineers per dollar. The declarative style doesn’t slow down web apps very much, it’s rerendering every component any time a state changes anywhere that does.