Competitive PvP is different than PvE. And I don't mean PvP where you're just grinding for crystals that you can trade in. All the suggestions here involving battle pass or trophy crystals do not understand that competing for a top 1, top 10, or top 100 spot is different.

The game mode could literally be as easy as checkers, but as long as there are a limited number of spots and there's skill involved, then the difficulty doesn't come from the game, it comes from the other players you are playing against.

That's why saying "the hardest PVE content" doesn't mean anything when compared to competitive pvp in any way.

As an example, I couldn't really care less about old BP rewards coming back, those rewards mean absolutely nothing. There is no difference between rewards like that and hitting a tree in the diadem for a mount. Top 100 rewards are completely different, and you are trying to bring those rewards down to the same level as a diadem grind.