Right now players are exploiting the mechanics for the boss dmg reduction.
The way it works is that we do around 190M dmg and with a big hit do a big jump that can go to 250m or even more than 300m depending on the team. This big jump does not get the 90% dmg reduce and after rhat the team keeps griding with the 90% dmg reduction.
I don't think is a good mechanics to be exploited. There is lot of RNG involved and tricks to get it working that way that has nothing do to with heros or bosses skills.
Would be better if you reduce all the dmg done above above 200m so this big jump exploit is not a thing.
It has always been that way with the dmg reduction, but the difference now is that basically every team can do 200m+ so dealing with this mechanics exploit with every team is a miserable experience.