That is just a bunch of baloney. I've flown UA transcon and US does not compare. US doesn't serve ice cream sundaes--UA does. US doesn't serve decent wine--UA does. US doesn't serve hot nuts--UA does. US doesn't offer a bread basked--UA does. US doesn't serve meals in courses--UA does. Not sure which aircraft you flew on, so can't comment on inflight entertainment.
Now, you didn't say that you flew UA in F, but I am assuming you did. If you were sitting in Y, then I can see you saying that UA is only a little better assuming you were not sitting in Y+
I was in F on UA. And, UA is really not that much better. The quality of the food was no better. Serving in courses quite frankly is irritating -- we were almost over Chicago before the meal service was done. Half the cabin didn't bother eating the ice cream sundae anyway. etc. UA is better but let's not base our total assessment on the whiners over at flyertalk.com. flyertalk.com represents a very small segment of the flying population.
Let me put this anyway ... paying for domestic F on UA is no more worth it than paying for domestic F on US.