WhatColorIsIt
I personally wish I had waited a few hours to switch over. I kind of am curious what stock Android on my Pixel looks like. I could have taken the time to play with it a little.
Others care a lot. They don't like the idea of Google "spying" on them at all, so they flash ASAP and never look back.
Probably not the answer you're looking for but it's your phone. You can do whatever you'd like with it.