I was going to mention that myself, plus even though a 4 layer BR disc can hold up to 100GB, it's virtually unheard of for the feature itself to occupy 90GB. So that stat strikes me as motivated reasoning.This conversation is also assuming a perfect scenario. There are so many links in the streaming chain that can affect bitrate and AV quality - ISP throughput, ISP throttling, in-home network speed, streaming device, device setup, time of day, etc., etc. What one viewer sees and hears may not be the same as the neighbor two blocks away. There is a LOT of variability.
For me, with my HT that is more audio capable than video (with a 65" QLED) and Gb internet with ethernet to my AppleTV 4K, I hardly see any real visual difference, but I do hear an audio difference, at least with action movies. So, in general, I've stopped buying streaming versions of action movies.