They are mostly software but the actual time critical RF stack isn't, those esp's have that in HW (at least their manual suggests that) and the remainig Bluetoo

They are mostly software but the actual time critical RF stack isn't, those esp's have that in HW (at least their manual suggests that) and the remainig Bluetooth or wifi stuff does not need to run in an interrupt disabled critical section, so can work fine with an time critical app, but naturally depends on how much transmissions need to happen and how time critical and compute intensive the application is.