Though I will agree that for most, solitary confinement is worse than gen pop, and can be classified as torture, I consider prison of any kind to be torture. For me, solitary would likely be better. I doubt my claustrophobia would be any worse than being confined had already make it, but I would know I was safe, and could spend my time exercising and meditating, without worrying about the power politics with the other prisoners.
I consider death to be preferable to any kind of prison. But I think I could survive solitary, whereas I would likely get killed in gen pop by other prisoners to whom I refused to bow in subservience.
But I haven’t actually been in prison. Reality is often very different from imagination.