I notice the heat on my left leg when the fan kicks in on the old Vee, can't say it's particularly bothersome though since your eggs are usually being devilled by the rear cylinder at that point anyway ;) Not KTM 890R bad though, that thing is like an air fryer with no lid.
I did notice some heat from the 800DE when I rode one at ABR but the weather was roasting and I was in jeans. I think any faired bike is going to have a point the heat exits the bodywork and I wouldn't be inclined to modify anything in such a way that the heat is held in.