Short answer: it's not a yes/no answer, they do vs. they don't, it's a question of percentages.
Long answer: it's impossible to generalize. Almost every tube preamp is going to have a different design/topology. Depending on a number of variable factors, you can make a preamp that uses just two tubes + ss that sounds better than one using eight or twelve, and vice versa is also true.
As 3-e-p says, beyond this you're getting into design philosophies that different designers hold up as being the best (or which suits them best).
Long answer: it's impossible to generalize. Almost every tube preamp is going to have a different design/topology. Depending on a number of variable factors, you can make a preamp that uses just two tubes + ss that sounds better than one using eight or twelve, and vice versa is also true.
As 3-e-p says, beyond this you're getting into design philosophies that different designers hold up as being the best (or which suits them best).