UFC payment vs Boxing payment

Lets put it this way:

UFC 268: Usman vs Covington 2 PPV buys= 700K
Boxing: Canelo vs Plant PPV buys = 800K

This event happening on the same night
Only 100k ppv buys different

But Canelo earns 40millions and Plant earn 10millions from their event

How much does Usman and Covington earns? I bet not even 5 million each. Maybe 1-2 million for each fighter.

How is their salary is totally different from the 2 sports? They basically get around the same amount of PPV buys.
I think UFC need to pay their fighter more. That's what they deserve.