What makes music so congested?

Normally reading it as you have put it, I'd blame it on the mix in the recording... why would several recordings be excellent having clarity and placement and one be congested? I haven't listened to this in several years as I have also moved more to Jazz, but I have many rock tracks that are still very good.

if other recordings sound good on your system, it's gotta be the recording. fragile has been re-released literally dozens of times since it came out and i'd assume that some of the releases are better than others--alot of early 90s cds very poorly mastered. my recollection is that fragile sounded great on vinyl and less so on its original cd release. if you're really into it, there's a number of gold disk/mobile fidelity and dvd versions avialable.

See if you find a British original LP of that and see if you still say the same thing (Atlantic 'Plum' label). The mix is OK FWIW, though its not going to be as spacious as many jazz LPs, its pretty standard fare for the period. Its not likely IMO that the CD is going to show any of that off.

If all sound is poorly portrayed,it sounds like you need more definition in your system. Ampr? Speakers? CD player? Cables? Probably it is all contributing...or perhaps you need to put your components on spikes, or other resonance control devices. Try different things you could borrow before buying.

Remastered US CD from a few years back is good to average or above average depending on track as I recall.

Need not sound overtly "congested" though often does from what I have heard over the years. So devil is in the details as usual.

Not uncommon for many small ensemble jazz CDs to sound relatively uncongested more often on more typical rigs than for many progressive rock albums, like Fragile, which are typically more of a challenge for a rig to relate cleanly.

If you are able to get a mixed bag recording like Fragile (even the original CD master) to sound clean end to end, most everything else will as well, but not vice versa.

Relayer is another Yes album , TGOD in particular, that is very challenging. I've had it on vinyl and CD since it first came out on each pretty much and only recently was I able to squeeze everything out of one of the more recent CD remastered versions. THe original vinyl always sounded pretty decent but all CD versions I have heard are a real challenge to surmount! If you get to the point where TGOD on CD, the battle sequence in particular, does not sound overtly muddled and congested (it is doable) you are then sitting pretty for most anything to sound at least decent. It's a pretty telling acid test CD not as a reference recording by any stretch but as a test of your rigs ability to decipher and deliver the music in the recording coherently.

TGOD is a 20th century rock music masterpiece to me, a real spirit cleanser when needed, so getting it right finally has always been a priority for me.