Why do so many people have problems with bass?

The room is key, but so is proper amp/speaker integration. I had great issues with what's known as one note bass, an overly resonant, booming bass in a couple systems some years ago. I tried to fix room with great use of tube traps, double stacked in four corners, moving speakers and listening position to avoid standing waves, nothing I could do to solve issue. I then concluded amp/speaker combo I used in both those systems was the culprit. I loved sound of tubes on mid and tweeters on both speakers, damping factor of those amps not enough to control woofer. I would have needed to biamp those speakers, tubes on top, solid state on woofers to get the coherent sound I was looking for.

Good bass is tuneful, articulate, opposite of one note, boomy bass. The other thing you'll find extremely noticeable once you get rid of boom is far more resolution in mids and highs than previously experienced, boomy bass covers up much of freq. spectrum.

And to answer your last question, while bass interferes with the full frequency spectrum, most room mode problems manifest in the 45-95 Hz range. 

Room size doesn't affect bass range even a car can support under 20hz as do headphones. Most bass issues are caused by overly small loudspeakers that have overly small baffles and little below 50hz many have a titled up response around 80-125hz so they sound like they have a lower bass response thank the BBC for that. If you end up with a space that re-enforces a lower frequency node multiple bass sources can greatly reduce it. As I type I sit in front of a giant with 4x21" woofers I use these near field most of the day in my office. I have no bass problems just great bass and pressurization of space.

Yeah it’s hard, for a lot of reasons - both limitations of the transducers and acoustic complexities of the room. I can’t stand thumpy / thwacky bass that sounds disjointed from the music - which is really easy to do, even with high end gear. I also can't stand soft bass or anemic response. And I use vinyl as a source, which can become difficult with too much LF energy. So my compromise is the 15" dual-concentric Tannoys I’ve got which roll off well before 20Hz, but have just enough extension to make "most" recordings sound musically whole.

A great set of headphones is a good tool that will reveal roughly how the bass "should" sound in relation to the music. Especially well-driven Stax. It won’t be as visceral or satisfying as decent reproduction on a 2ch, but it will tell you if you’re way off. Like headphones, the Tannoys do a great job of sounding coherent from top to bottom.

Also I think a lot of audiophiles fall into the trap of buying bookshelf / monitor models from a higher line so they can afford the better drivers (etc), or for size constraints (WAF), and then have to deal with the lack of bass or the headaches of integrating subwoofers. Which makes them fixate more on bass as a separate entity, which is a path to audiophile hell.

In general I’m pretty happy with my current setup, but I wish there was a way to make album compression more uniform. (I’m not sure if compression is the correct word)

So I am a Bill Evans fanboy. A nice simple jazz trio. Piano, drums and upright bass.  So I turn on an album and it sounds great and on the next album, a ceiling vent, 25’ away starts buzzing to the beat. And here’s the thing that puzzles me, I generally don’t play anything past 75-80 dbs , I’m not using a subwoofer and my speakers are isolated. So it has to be the recording, right?