RF is harmless below the point where it directly heats tissue.
Having a full strength cell tower transmitter inside your home is not safe due to the intensity of the transmission, it will directly heat tissue inside your body.
I think the distinction/point is that it's not harmful in the 'this might give you cancer' way that ionizing radiation sources will. Worst case, you get an RF burn... which is not great, but it's effects are immediate and obvious, unlike ionizing radiation which is much more insidious.
Microwave RF that is somewhat directional behaves a lot like laser light.
If you were to step into the beam carried by a waveguide for something like a powerful TV transmitter, it will cook you through like a death ray out of science fiction. Fortunately it's not actually collimated, so just a few feet away the energy is barely enough to cook your retinas faster than your blood supply can cool them (which can cause blindness). Otherwise, yes, it's much like infrared heating effects. If infrared penetrated a few centimetres deep, anyway.
Having a full strength cell tower transmitter inside your home is not safe due to the intensity of the transmission, it will directly heat tissue inside your body.