Because you're thinking about real tennis fans, which are a minority. The majority are gloryhunters/player fans. You see that phenomenon on MTF too; a good % of posters are not tennis fans, but fans/tards of *insert top 4 player here*. This kind of fan is the majority and the target audience, you don't want them to be interested in tennis per se, you want to give them superstars to bandwagon/idolize.
There's also sponsors of course: what better way to hype up the sport to the sponsors than with this golden era with amazing top 4 BS?
Real tennis fans want things to change, but unfortunately the $$$ doesn't come from them.
I thought more people hate the top 4 than vice versa
I guess not
It seems like a marketing strategy that only 6 year olds would fall for
We need a revolt, and we need one now!