The bulk of that 12 hours was actually spent debugging negotiation and timing/race issues in the signaling/SIP layer. Even for me, figuring out how the WebRTC API is supposed to work was a little difficult.
Often veterans here will talk about projects they trivially did. but unless you dig into their profile and find out who they are it feels like every joe-shmo on hn is a 1/2mil+ SWE at google.
My point is that a whole 75% of the time I spent on this project was just me flailing around with stuff that wasn't working as I expected (that's relatable at all experience levels!). Perhaps it's true that veterans can get through certain things more quickly than novices can, but we're not immune to the 80/20 rule either! We just get stuck on different types of problems.