You are likely to get different recommendations from every response. I am not an expert, nor do I claim to be. I can only speak from my experience and research along with I believe has worked for me so far.
I do the first oil change at 1000 miles (I don’t see anything wrong with 500 though). Then I change it again at 5000 miles. From there forward, I change it every 5000 miles.
I generally won’t consider UOAs until I am at 15,000 miles. At this point it seems that everything is beginning to settle down after break in. I typically will do UOA from 2-3 oil changes to get a solid baseline. A lot will depend on your conditions and use. I’ve always been ok with the results that I get from these 5,000 mile OCIs. I have no interest in extend drain intervals. After I establish a baseline I will send off for UOA every 20,000 miles for condition checks.
Once again, YMMV. This is what I am comfortable and confident with. You are probably right, all of us involved in conversation like this is way overthinking it. Few take the time for any type of analysis, yet we don’t see cars sitting everywhere with blown engines. I have always taken care of my vehicles, but have only gotten more ****** about it with age. I never did any analysis on my Silverado that I traded with almost 400k miles on the clock, or a couple of F250s that were pushing 300k when they were sold. All vehicles just received routine maintenance with quality products.