Indeed. And even so, the interaction of magnetic pickup, stressed/worn tubes, and borderline feedback becomes an instrument in and of itself, that can be manipulated by how the player handles the strings, changes pickup settings, and moves around. I have played with a few simulators, and they lacked that flexibility.There is DSP available to simulate tube guitar amps. I highly doubt you can get there with just EQ. Often the amps feature sagging screen voltage and other distortion mechanisms.
I can imagine listening to music that way (much like a DJ will blend and alter records together), but it isn't my particular cup of tea.