I think people reference pros because they are looking for validation of their own views. I still see the same people playing the game on Twitch as last season. It's not bringing a lot of people back that left, but it's doesn't seem to be losing anyone that stayed with the game.
It doesn't seem to me like TTK is a real factor in whether people stick with Apex or not. They have mostly left due to newer games coming out with new experiences while Apex has mostly remained the same basic gameplay experience. No new map since beginning of Season 3. Season 4 changes weren't that great. Season 5 likely made more people mad than anything with blowing up Skulltown and Thunderdome. No new ways to play these maps. No PvE content which was long rumored since Season 1 to be happening.
I don't see people returning due to TTK, just maybe to check out the new Legend and map changes.
Whatever you may think of Warzone, it did a lot to shake up the BR formula, not unlike what Apex did when it launched. Warzone has much higher player count, on map objectives, the Gulag, and Plunder mode allows you to play the map in a respawning environment. Tired of cheaters and BR? Play Plunder and explore the map a leisure.
Valorant is the other game I've seen players gravitating to. It seems to have successfully combined hero gameplay with CS Go level competitive play.