Watts are only one parameter, and an easy one to market, like Megapixels in Photography. I remember back in the 60s when solid state first got started. The marketing drive was how many transistors a radio had. The more the better so the more it sold.
My current 40 watt mono block tube amps drive the few speakers I own better than several solid state amps I had that had more than double that power. I'm not implying that tube watts are always better than solid state butin my current set up, it has proven to be. There are so many other factors like current, power supply, that affect the ultimate outcome.
Finally, current tube gear performane, as shipped from the manufacturer, is likely constrained by currently available production tubes. It has to be that way as amp manufacturers needs big quantities of tubes, Although the current tubes available are decent and better than 10 years ago, numerous older tubes have further significant positive impact on the sound.
My current 40 watt mono block tube amps drive the few speakers I own better than several solid state amps I had that had more than double that power. I'm not implying that tube watts are always better than solid state butin my current set up, it has proven to be. There are so many other factors like current, power supply, that affect the ultimate outcome.
Finally, current tube gear performane, as shipped from the manufacturer, is likely constrained by currently available production tubes. It has to be that way as amp manufacturers needs big quantities of tubes, Although the current tubes available are decent and better than 10 years ago, numerous older tubes have further significant positive impact on the sound.