In my view the tube industry in the 1960s/70s saw the writing on the wall: Solid state designs were becoming affordable, more durable, immune to microphonics, pretty much never needed re-biasing, were smaller, more efficient, generated less heat, and had great sound quality with typically, as a class, lower noise/distortion and a flatter frequency response into an actual speaker load. . so they realized their days were numbered and their only shot at staying in business was to move the goal posts and start selling instead based on mysticism, snobbery, elitism, and marketing lies. Examples upon request.
The most prolific amp reviewer who has ever lived, and who tested, measured , and listened to first tubes (because they were all that existed when he started his very long career) and then later solid state designs, wrote back in the late 1990s:
"Have you ever wondered why vacuum tubes are still so much in demand for high-fidelity components? I have, but so far I have not been able to come up with a convincing answer."
Source: "
Remember Vacuum Tubes?", Stereo Review magazine (later renamed Sound and Vision) Feb. 1997, p.24
There are all sorts of reasons to explore tubes*—nostalgia, looks, room heater, etc.— but it annoys me that people are being lied to by marketers and I know this from firsthand personal experience because I was one myself, so I know exactly what the tube marketers (and my tube companies' reps) push.
*Just like there are all sorts of reasons to ride bicycles even though we now have cars, but a line has been crossed if a bike maker lies and tells consumers, say: "Bikes have better acceleration than cars to those of us who are discerning".
