@cleeds,
Generally speaking, Your impressions are very similar to my listening experiences as well when comparing both streaming and vinyl. The main difference to me is that when a half speed mastered produced album has been treated with all of the aforementioned attention to detail that makes it worthy of a standout album compared to others. Otherwise, the half speed master is just that, a half speed master. I have been purchasing the newer MOFI half speed masters off and on over the years and it seems hit or miss in terms of sound quality. Some sound flat sounding missing dynamic range, while others sound absolutely outstanding.
It is absolutely in the entire recording process and the quality of the source material. I purchased a Barnes and Noble special edition Queens greatest hits album that is absolutely stunning regarding its sound quality. It is not a half speed master album either. I also have a regular store bought Sade album from the 80s, thin vinyl, not half speed mastered, that is also stunning. These are standout albums compared to some of the half speed masters that I own.
I am also certain that the recording engineer may be part of that equation. To me, it appears that Quincy Jones produced albums almost always with great sound dynamics without any sense of compression, just pure music. Michael Jackson Thriller and Earth Wind and Fire are examples of normal albums with very good dynamics that Quincy Jones produced.