So...you do use the grappling hook in episode 1, you just need to do, y'know, the climbing part.
Health isn't used in the traditional sense of an HP bar, but if you take damage then it affects how much you level up after the episode is over.
I'm continually puzzled by you being convinced there's not skill checks in the game. No matter what path you take through episode 1, there's TONS of skill checks, and you get notifications for what you've failed or succeeded at.
In progress interactive fiction games are browser based all the time, just look through the rest of itch.io's library. Using DDLC is indeed a horrible example for this, because you're comparing a game that intentionally is made to look like a traditional visual novel dating sim with an interactive fiction game, which plays much more like a digital choose your own adventure book.
So much of your "this is definitely AI" proof is just "it feels that way" or "trust me bro".
But as someone else said, the development of this game AND the design of it's UI predate the widespread use of AI/LLMs.
If you don't think so, then I can't convince you. But trust me bro.
Do I need to continue?