Comments from an old fool:
I grew up playing in the sixties, through tube amps made in the sixties by Vox, Fender, and Ampeg. I transitioned to solid state amps in the late seventies, and have gigged nothing but solid state amps for more than 40 years because of the size and weight of tube amps. I still own the Fender and Ampeg, but they stay at home.
When I think about my experience playing through amps from the sixties through today, it's the feel as much as the sound that I remember most fondly when I think about tube amps. The dynamic, touch-sensitive, interactivity of those old tube amps has been very hard to achieve with other amps.
My experience listening to others playing through tube amps leads me to conclude that, to me, the feel of playing through a well-made tube amp is at least as important as the sound.
With a good tube amp, I feel as though I am interacting with both my bass and my amp.
With a good solid state amp, I feel as though I am interacting with my bass, with the amp merely processing the resulting sound; it still sounds good, but it feels uninvolved in the touch, feel, and development of the sounds created.