Having begun to experience hearing loss and concomitant tinnitus in my 60s, I finally opted fir a set of (relatively) high-end Phonaks, which were computer-tuned to audio spectrum of greatest loss, round 4000 Hz, +/- 500 Hz. Listening to a variety of music on a “mid-fi” rig there is a clear improvement in overall detail in the mid-frequencies, with little difference noted in the two extremes. Now, with hearing compromised, it doesn’t seem worthwhile to go all-in spendy for system upgrades, as the gain in detailed nuances would probably be washed out, or somewhat distorted by the hearing appliances. However, I would be interested in hearing from audiophiles who indeed have compromised hearing, use aids, and can ascertain sonic differences between various pieces of hi-fi kit as one moves up the quality ladder.
