...internal heating of the body of the sensor is a start
Well, if you think that making the AoA sensors pressure wash proof - yes. But why? There seem far more fundamental issues to address to prevent a "repetition" which is the aim...
I suppose it comes down to whether the "basic cause" of the accident was HF based, or Technical? To "blame" the AoA sensors means Technical. To me, it was a HF accident unfortunately.
As I said, I fly A320s for a job, with Pax down the back, in all sorts of weather. I have no cause for concern over the AoA sensors as fitted.
NoD