Fractal appear to go with refining previous designs while keeping functionality/options. My old R2 mini has 6 removable trays on matx.
I can't really work out much from the pic, but i guess it's just a possible option if you opt for passive intake, or maybe a short rad on the front. Looks like it takes a 140mm also? Would be make sense there also.
They also do 120mm adapters, fan fitting to hard drive. So yeah, options.