Well, in truth most other people are way too polite to say so to your face.
They mostly use anonymity there, or snipe to others about your obvious deficiencies as a person.  

Make no mistake, it isn't everyone, by any means.  But for some parents that really 
do seem to measure their self-worth by some cosmic competition to see whose kids are "better" than theirs, this is pretty much a given.  
THOSE people are absolutely toxic to parents of GT kids.  They'll dig and dig for ANYTHING that seems to be a potential flaw in you, your parenting, or your child... and then crow about it.  Passive-aggressively, of course... so it always 
sounds as though it is "concern" for your family.
But it isn't.   (I find that kind worth active avoidance myself.)