You think that players are just going to accept wage reduction clauses in their contracts because they are nice guys.
Why doesn't every club use them then



"Oh hey, we didn't win the league this season so your wage just went from 150k to 100k, you're cool with that right?"
"Oh hey, we didn't make Champions League this season so your wage just went from 100k to 70k, you're cool with that right?"
"Oh hey, we didn't finish in the top 10 this season so your wage just went from 70k to 40k, you're cool with that right?"
I doubt there are ANY player contracts outside of those clubs that are a good chance of being relegated that have anything resembling a "wage reduction" clause. To think otherwise is bizarre and not based in reality.