bump!!!
doesnt even matter if he used an LLM, i use them all the time to crank stuff out like this. YOU still probably wouldn't be able to do it though with "ChatGPT", without any developer experience. most people that say that it's easy, would give up before seeing it through.
and you can tell by his screenshots that he put his heart into it; for example
these progress bars - could've easily implemented it in a simpler way, just display a percentage number. but nope, he made it show you little graphical indication bars with emojis. that's attention to detail, experience, creativity. stuff you cant just get ChatGPT to imagine out of nothing.