A few things I learned that may save someone time:
(1) Sound quality is in the medium, not the build. Speakers almost always sound better than a pair of cans (headphones), headphones almost always sound better than IEMs, IEMs almost always sound better than over the ears.
(2) The difference in sound quality between something that is a few hundred dollars, and something that is a few thousand is so small that "diminishing returns" as a phrase doesn't do it justice.
(3) The stack of DACs, EQs, preamps, and neatly managed RCA/XLR cables looks cool on your desk - but they take up a lot of space and cost a lot of money for something that sounds maybe 10% better than a pair of AirPods Max (provided you remember to turn on lossless in apple music, which I forgot to!)