Sp has not insulted gk directly but he has many times in his interviews said mean things about gk's character and that its not a big deal or doesn't require much of acting prowess to portray anuj while vanraj's character is multi layered and it demands hard work and experience...something on these lines. So in a way he had many times undernines gk's talent. But gk on the other hand has always said nice things about sp and vanraj.
But i agree that sometimes fans take these things too far and on their own start fan wars.
But if gk and sp are not enemy then definitely they are not good friends as you have mentioned. Like fan wars, this made up zabardasti ka friendship is also result of delusional fans.
I think gk and sp just share professional bonding. They are colleagues....that it.
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