90% of max damage wouldnt make much of a difference. Even the gap for 331 to 365 doesnt matter that much, Even 365 reduced by 10% would come out approx 328.5, not much lower than 331. Its still in that range of for high end PVE and much more by PVP, there really is no difference. The gap is paractically insignificant. People would still use them because a gap of like 10 or 30 damage per shot or rather 1 to 3 in pvp lets say, will not make a radical difference. People would still be using fatebringer and vision of confluence and otherwise found verdict, word of crota, and hunger of crota, without much incentive to see the new content, PVE or PVP. So get used to the new stuff.