To be clear, I'm not a schill for the tube amp industry. I can't handle the cost and maintenance and cost of good tube amps. I just don't deny that there is something substantive to the tube sound. I don't think saying that tube lovers like listening to distortion machines is necessarily correct. I have done some online hearing test things before where they introduce a signal which would be equivalent to 1%, .5%, .1%, .05% and lower distortion. Could be my age, but I have a difficult time hearing the .1% signal if i'm not imagining it, and below that I hear no trace. I give more weight to the linearity and imd graphs posted here than thd.Linearity is measurable as low distortion.
SS amps in general measure better than the best tube amps. Those tube amps are never single tube designs and have lots of feedback (local and overall) often including extra windings or on just one of the TX taps.
Its all in the implementation of the active devices in a complete physical circuit.