Killer sound as is
Did it sound "better" sometime in the past?
Very much doubt so.
*Tubes* age, every second they are ON some atoms boil off the cathode coating , eventually said chemical coating gets depleted and tube is too weak to function properly.
In the long road between fresh out of the box and the corner dumpster, sound is changing all the time, while Transistors either work or die.
So power transistors are the last in a LONG chain of suspects, including strings, pickup settings, cables, ambient humidity and temperature, other instruments playing along, wall voltage and 1000 more, not forgetting signal generator (Musician) or Meter Microphone and processor (Musicianīs ears and brains).