There is no way to know tennis is clean given that the doping testing system is effectively nonexistent, so bluntly stating you are proud of the cleanliless is nothing short of ridiculous. If he was defending tennis he would talk about that.
He just said that until proven guilty it should be considered clean. I mean, lately there are all these rumors and apparent drama, but we see no names, no actions, nothing.
I have to agree with him, either put up facts and proof or stop the pathetic rumors and gossip that are only hurting sport in general, not just tennis.