95% of the work engineers on this forum do are high level apps like a "music blog", and not car firmware...

And then there's the small % doing music firmware :)

(and no, I don't find LLMs much use on this)

It's not a blog - it's a community website, so significantly more complex (running competitions, uploading tracks, moderation, etc, etc, etc).

I don't understand the car firmware non-sequitur. I've already seen productivity gains in this domain. Why do I need to also prove them in another one? They are already demonstrated. It's like me saying "I can get places faster in a car than on foot" and you're saying "yeah but you can't get to the moon."