I learn faster, and much, much more comprehensively, these days, than I ever did when I was younger (I suspect because of the vast context I got from experience). The main reason I'm doing my own thing, is because I love learning so much, and I see there's a whole world of stuff to learn.

StackOverflow is a critical tool for me, but only a reckless madman would stock a majority of their code from there. I use it to solve occasional vexing problems, from time to time, and always modify the (usually tiny) snippets I may glean from it.

All the rest is mine. I've been writing original code, often far ahead of its time, since the 1980s.

I would have been happy to work for a fraction of the salary a lot of folks far less capable would have asked; simply because I love doing this, and the challenge of the job would have been the most important coefficient.

But that's water under the bridge, these days. Once I accepted things the way they are, and just started doing what I wanted, on my own, I became much happier.