Even without doing insane pepomath with r.io data / wlogs data / keystone.io data etc etc to estimate the number of player, which is roughly 1.2milion atm, that doesnt actually tells us the quality of a game even if WRATH had 12milion players.
We saw a shifting trending from WOD to SL of players quitting because convoluted and grindy systems repeating each expac, and how easily the dev team restored tier sets or swapping covenant or conduits energy after a huge sink of players the last Fall.
Also the fact that Classic got a way larger success than Shadowlands, for its super short lifespawn, for a game that had basically the "kill boss get loot rinse and repeat" system, something means and not "ehuehuhe PiNk TiNtEd GoOgLeS"
- - - Updated - - -
Toweliee is probably one of the few streamer that actually lives near Blizz HQ and hang out with them, so he is allowed to give some "bits" just to keep the hype.