The JS I travel is not at all punctual. So ICE.
JShtb and Intercity shouldn't be compared. Intercity (s) are popular on short routes whereas JShtb are popular on long routes with high priorities and also time taken are almost at par with Shtb(s).
But still casted my vote😋
Well, there are examples where JS and ICE run in same route and those ICE's are themselves very famous. For example, Siddha Ganga ICE, Pinakini, Dhauli, Steel etc.
Jan Shatabdi knocks out Intercity 👊