The most important thing to understand here is that these people are NOT actually that amazing! They are a wide spectrum of coders, artists and musicians of widely varying capabilities.
What people do have is some very PARTICULAR skillsets. You can pick up those skills too! People will help you out if you ask! You can learn all these tricks if you want to. It takes some effort and inspiration, but it is doable for most people. It's not magic, it's just learning things. Things that are often utterly useless, but fun!
It's also important to note that we only see the end result, and not the 100 iterations before that evolved to the final, impressive version. Very few developers could just jump in and code what gets published.
That said, if you watch some Shade Showdown competitions on YouTube you'll see demosceners effectively doing exactly that. It's quite intimidating how good they are.
I think very few people are able to hold with the 100+ iterations of improvement... This persistence and the quality of the result are where they are amazing.
Skills can be taught and learnt, but obstinacy is a quality that cannot be developed just by anyone, it is a character trait.
What people do have is some very PARTICULAR skillsets. You can pick up those skills too! People will help you out if you ask! You can learn all these tricks if you want to. It takes some effort and inspiration, but it is doable for most people. It's not magic, it's just learning things. Things that are often utterly useless, but fun!