Agree with the overall premise. In regards to that first experience...
> In addition to all the coding, I had to deal with the manual, give press interviews, and all the other founder things.
I find that this happens because coding is somehow still underestimated even though everyone knows it's hard but it still gets underestimated and so it is never the sole task for an individual but among many other tasks which takes away from the focus.
This is common across the industry, with most engineering roles involving all kinds of non-technical tasks even though the coding part is the most crucial. You would think that if coding is so important that you would optimize that role to only focus on just coding such that you get the best quality in the shortest amount of time, and all of the non-coding tasks can easily be done by anyone that doesn't have the technical skills which should be a lot easier to hire for.