Yes, it’s an upgrade and GRIP is better than motion control imo. A small weight saving too. The rhythms will be stiffer than the 32 stepcast too, but heavier. So only really worth spending lots on the 32 SC if you need the weight saving. If not, the rhythms will be good.
Another small consideration is that the rhythms are far better in claggy mud than the 32 SC as the whole fork is wider, like all boost forks, giving more mud room. Stepcast pulls the legs closer together so clogging at the arch in claggy conditions happens, unless you run narrow tyres.