The entertainment industry, which WWE regards itself to be in, does not generally equate the most popular to being the "best". For examples of this in real life, feel free to read this Wikipedia entry:
https://en.wikipedia.org/wiki/Leonardo_DiCaprio
The "best", being a subjective term and "most successful" only correlate in competitive business where the only factor is sales. Is business entertaining? Trends point to no, as shown by this totally relevant graph.
You are arguing that WWE does the best business, which is true, however you are passing this off as proof that WWE is the most entertaining. Numbers are not considered entertainment to most people, with less than 15% of audiences reacting positively to numbers, while in some cases statisticians struggle to figure out of the numbers are being laughed at or laughed with. Is James Cameron's Avatar the most entertaining cinematic release of all time? Is an episode of shoddily acted TV Soap "EastEnders" from 1986 the best thing ever shown on British television? Does having more reputation points than somebody make you an unquestionably better poster? Is the oxygen tastier on the peak of Mount Everest?