Nonsense. How did the attendances of other Dempsey' contests in the '20's go. PS, That picture was New York, not Paris.
I don't doubt that boxing is as popular as ever in certain countries. I wouldn't call it GLOBAL popularity though. Global would mean boxing in every country would be enjoying peak popularity or something close. But .... even with all that at hand, very few people do that now. Sorry, but we're in a minority. From the 20s, all the way through to the 70s probably, a big fight was a BIG event, and bound to be the leading news story, outside of a world war being declared or a president being killed or something of that magnitude. Most people I know will not be rushing out to buy Pacquiao-Mosley or even aware that it is an upcoming event. And they wont be rushing out to buy the paper or switch on the news to find out the result. Dempsey-Carpentier, Ali-Frazier : those were huge events. And all boxing world champions were sports STARS. Even top contenders were household names. In the UK, even domestic British champions were known to every man who followed even a little bit of sport. Nowadays that is not the case.