Volume Increase of decrease as system improves

I would agree.  As the sound of my system becomes clearer and cleaner I do tend to listen at louder levels than before. Really fine software whether vinyl or digital, also tends to lead to louder levels.  One thing, my experience is that every indoor listening space has a maximum volume it will tolerate.  If you get carried away with the volume, the sound becomes cacophonous.  Ugh!

As I improved my system, the volume level I listen to has gone down.  My system sounds dynamic and lively without relying on high volume to deliver juice.

Maybe you're getting older with declining hearing acuity.....

Distortion is interpreted as loudness so less distortion means louder will still sound good. You need a good recording without distortion as well as a large dynamic range to want to crank it and still find it engaging and enjoyable.

Some of the speakers being touted as neutral today are a lot brighter than neutral, so you'll have a tendency to keep the volume lower. Or so I think. :)

There's nothing wrong with tailoring a speaker to be played at lower volumes, in fact it can be quite useful! But I think that's a little part of it.

More neutral speakers may sound a little less bright at low volumes, so you want it up.

BTW, I don't personally care what you personally like... so long as you are happy. :) I'm only trying to explain a possible cause and effect.

Best,

Erik