The biggest thing that sticks out to me is that if you expected to spend more than 3 hours a day writing code as opposed to simply thinking about it / studying it / discussing it / debugging it, you may have been misguided on what a coding job would be. I've only worked on relatively small-headcount projects, and even when the only code in the repo was my own, most of my time is spent debugging things, reading datasheets and discussing design choices with others. Actual writing of new code is fairly minimal, especially after the point in the project where you're making feature changes & additions. It takes a lot of time to figure out what to change without breaking everything!

I have to imagine that a job that allows for 8-10 hours of pure coding (not debugging, not discussing design, etc) every day has a boatload of half-finished-but-not-operational projects sitting around, waiting to be tested & completed.