Amplifier design philosophies were different among manufacturers of the day. Where many manufacturers would cut and paste application designs from the RCA Tube Manual for a quick go to market strategy, others (like Sunn) would design the preamp and use off the shelf power amp designs such as Dynaco for the output stage. In the case of Ampeg, they would seek availability of surplus military tubes (often cheaper) and design around them for better cost margin.
The fact is, tubes were the only alternative back in the day. This said, the interesting serendipity of using tubes for guitar amplifiers came from the fact that in guitar amp combos where the tubes are mounted upside down in close proximity to the speaker, resulted in a mechanical feedback effect from the speaker to the tubes adding yet another dimension to the tactile feel from the amp to the player. One that modeling amplifier manufacturers tried to emulate with limited or no success over the years.
For us bass players on the other hand, clean power is what we seek. The fact that guitarists thrive from these intentional and unintentional effects of tube power should be of no consequence.
Bottom line:
Overdriven Ampeg SVT's, Sunn 2000S's Hiwatt 200's and other bass tube amps sound great when playing quarter notes.
If your playing requires any type of agility, go SS.