Basically they are stuck in the classical mess of TKD.
They may be "black belts", but they are black belts in TKD - if anybody does something that is outside their comfort zone they are white belts again and don't like it.
The way you deal with the kicks by pat down block is good - it floors the energy. Of course they don't like it. They of course will not like you doing things that are "not TKD" and nullifies their technique.
It's also why they are messed up if you close to punch range. Try doing a clinch and HKE and see how they like it. You will be told not to do it "coz it isn't TKD" - the TKD "black belt" hasn't got any method of dealing with it.
In STMA we use savate at the long range.
It has all the kix TKD has as well as all the low kix.
And at punch range it has all the punches of boxing.
And it is designed as an FC sport, not foam on foam SC.
And it is derived from a Street art. TKD is not.
Bottom line - a STMA blue belt is a far better fighter at kb range than a TKD black belt.
He will also be a better fighter at grappling range than a Judo or Jujutsu black belt.
And better at chi sao than a Wing Chun man.
Reason - STMA man has all the structures and is bound by none of them and moves from a place of spontenaity not from a list on a syllabus.