I disagree Tricky.
Professional wrestling is entertaining for millions of people and calling an individual who excels at entertaining people "great" seems reasonable to me. Professional wrestling is a cheesy melodrama, but it is a melodrama that most of us are entertained by at least on occasion and some of us enjoy a great deal. (Most doesn't include my wife, who is completely disgusted by it).
Perhaps your point was that the term "great professional wrestler" or "great performance art wrestler" would be OK but "great wrestler" isn't because the term implies that professional wrestling is a competition sport. I disagree with you there also. The term "great wrestler" used in context isn't ambiguous and doesn't mislead the vast majority of people. For the few that are mislead, I say fine, let them have their illusions.