This isn't like making a Mario game that's a sim, it's like making a Gran Turismo game that's a platformer. The entire appeal of the X-com franchise is the gameplay. The setting is generic and fairly incidental.

I'd rather have something that played like X-com, with a fantasy setting or a gang warfare setting; than a generic first person shooter with the X-com name clumsily stapled on.

The only reason I can think they're making this game is trademark renewal.