They ain't gonna do more "classic" Arkham games cuz those games had single player. What they are gonna do instead is create some Arkham multiplayer garbage with microtransactions, DLC and loot boxes out da azz.
The sad part is that just like Destiny 2, GR Wildlands, R6S, ME:SoW, CoD, BF1, SWBF, Division etc. people are gonna buy it like hotcakes, too.
Single player is dead these days. It's gonna take a number of costly failures to reverse the trend (hopefully soon).