I think part of what's been happening here is that the hubris of the AI startups is really showing through.
People working on these startups are by definition much more likely than average to have bought the AI hype. And what's the AI hype? That AI will replace humans at somewhere between "a lot" and "all" tasks.
Given that we're filtering for people who believe that, it's unsurprising that they consciously or unconsciously devalue all the human effort that went into the designs of the apps they're looking to replace and think that an LLM could do better.