Saying that the UE was "optimized for shooters" might have been true ten years ago, and even then, it was mostly a really efficient, modular general-purpose 3D engine more than anything. These days Epic seems to be making a push towards billing UE as a development suite for just about everyone in order to compete with Cry and Unity and in order to keep their business relevant since the Gears and Infinity Blade ships have sailed.
Need I remind anybody that Injustice and MK9 run on UE3? Still, an engine designed specifically for fighting games (like Skullgirls) is always going to be more technically efficient. The problem is that doesn't really matter much to the majority audience. Don't we have enough fighting games already? KOF, BB, GG MvC3, AH, SF, all very high-quality games. The genre has never seen higher production values and yet it can't make the sales to justify the costs. I guess a lot of it has to do with marketing and aesthetics.
Also, Epic doesn't care about their past, and OMF reboot will never, ever be a thing.