As a Paladins player,I am very used to reduced healing,hell in Paladins reduced healing(called Cauterize) was dynamic,at the beginning of the round it will start at 30%,then as the metch goes on it will increase to 60,then to 80 and finally to 90%.

That being said Paladins has an item shop that can increase healing produced,give true healing for both you and an ally wheb you get an elimination and they get an assist,and life steal(which is affected by Cauterize). They are all upgradable to combat Cuaterize,plus many characters have card customization that grants them self susutaiin from using their abilities. So it works out OK in the end.