What's up with lousy bass on classic rock recordings?

@macg19 looks like you got the bases pretty well covered.    It does look like a larger room.  Have you ever measured using white noise?   That gives a good idea of frequency response and room acoustics. If white noise is not flat down to 20 hz with the subs in play,  then try adjusting the subs accordingly.  
 

Then you will be in a very good place to assess bass recording to recording.   Of course each will be different and range from lots of bass to virtually none.  Recordings are what they are.   If you have digital files you could always try remastering things yourself using readily available software like Audacity for example.   I use Audacity to master digital I create from my vinyl record collection. I’m sure there are even better ways.   Just a thought.   Where there’s a will there is often a way. 

@macg19 Tell me a specific classic rock track and I will give it a play and let you know what I hear and also stick the meter on it. 

@dmac67 Also I think it’s worth noting that when producing classic or any pop/rock recording, lots of bass is not always a priority. Producers and engineers and the artists they produce for are looking to emphasize different aspects of their music all the time. There is no audiophile in the room saying that they must maintain the bass levels no matter what. Recordings are what they are ie what the makers want them to be. It’s not a democratic process where the audiophile party rules.

The OP may want to get acquainted with discogs to learn what to look for in a period press. 

It's all in the matrix.

Arguably, a first press IS the definitive version of any album.

Van Halen's debut isn't a rare, obscure album to find. The rub is finding one that's unmolested. 

Van Halen – Van Halen (1978, Winchester Press, Vinyl) - Discogs

Boston – Boston (1976, Vinyl) - Discogs

The Who – Who's Next (1971, Vinyl) - Discogs

Find one for cheap in the bins,or pay for someone going thru a dozen used copies to find "the one"  @better-records.com

@mapman I don’t have a white noise generator and the SPL app only measures down to 31Hz, so thanks for the offer!

Baba O’Reilly (I’ve tried HR Quobuz and I have it on vinyl) and VH 1 Running with the Devil and Eruption (Quobuz - no vinyl)

But I really do think it’s the recordings AND the SQ/dynamics that I now prefer.

EDIT: and as someone pointed out some of this is meant to be played really loud, and I try to keep peaks below 90dB

Back in the day my car had a better stereo than my home (JBL 6x9s - no one had subs back then with an Alpine head and amp in the trunk) and what I have today far surpasses anything prior - and it’s all relatively new gear.