I tend to agree - in broad principle - but I always put the dividing line at "what the artist, PRODUCER, AND MIXING ENGINEER intended".
With a lot of modern music there is no single "input".
Very few recordings these days are created by "putting a microphone or two in front of a performer or band and recording what they play".
Most modern music is multi-tracked.... which means that the individual musicians may have been playing at different times, or even in different places, and there may be lots of over-dubbing and re-dubbing.
Likewise, modern music often includes things like synthetic sounds, highly processed samples, and other special effects.
In many cases, I would have to include compression as "just one more thing that can be done to sound that sometimes sounds bad to me".
I tend to draw the line at the master - or at the CD.
If the producer, or the engineer, or even the artist, specified compression AS PART OF THEIR ARTISTIC VISION OF THE PRODUCT, then it isn't distortion.
Even deliberate clipping doesn't count as distortion IF IT WAS DONE DELIBERATELY AND INTENTIONALLY TO PRODUCE A CERTAIN ARTISTIC EFFECT.
As far as I'm concerned, anything of that sort is simply a disagreement between myself and the artist or producer...
I have a perfectly clean and undistorted copy of exactly what they wanted me to have.... and I simply don't like their style.
Have you ever looked at a Van Gogh painting?
They don't look anything like "the real thing".
And, personally, I don't like them in the least.
However, since they are also clearly what the artist intended, they aren't distorted.... I just plain don't like the artist.
(It would be different if Van Gogh painted accurate naturalistic paintings and we were talking about bad reproductions.)
So, to me, the unfortunate thing is some combination of:
1) a lot of people really LIKE highly compressed sound (or it catches their attention in certain situations)
2) the artists and producers BELIEVE that to be the case
Unfortunately, the way modern music production works, we often don't have much opportunity to make our feelings on the issue known.
With classical music, you often have a choice of several different performances of the same piece, and even different recordings of the same performance.
This means that you CAN avoid a certain record company, or a certain mixing engineer, if you don't like their stylistic choices.
However, with most other music, you have little choice.
It really isn't practical to avoid purchasing albums by your favorite group because you are dissatisfied with the sound quality.
In most case there isn't an option to buy a better-sounding version of that same group somewhere else.
At best you can speak up whenever possible and hope someone is listening.
If we define distortion simply as something at the output that was not at the input, then compression IS a form of distortion.
I DESPISE recordings with artificially squashed dynamic.