What I've found, is that using that picture and going "omgawfulunrealistic" is very often a result of a fundamental lack of understanding what the situation in that kind of TB situation represents. And that's not a jab at people's intelligence, just a showcase of lack of experience and/or knowledge of those kinds of games.
I.e. what's going on there is not the alien standing still and the trooper pressing the gun at his forehead with only about half the chance to hit. What it represents, however abstractly, is a specific, very very small fraction in time where the adversaries are only momentarily in that postiion. And if it was real time, the situation would continue in the alien attacking and the player not even noticing that that still was ever there. The game gives the %-chance based on the event that is taking place (the troopers skill with a gun against the aliens movement at that point -- it can cover reaction times, accuracy, tactical movement skills and speeds, if those stats are present).
And TB combat can be infinitely more "realistic" than realtime, because it can take into account every little thing from hurting a toe, to wind blowing to the combatants eye, to stumbling slightly to a small rock on the ground, and make it affect the outcomes in a very precise manner based on the combatants skill, and so that the player notices it. That can not happen in realtime combat where the combatants movement is obscured by the limits of the method of controlling him (mouse&KB or controller), and the limits of the players preception in relation to the screen and speed of the situation, that little details like the ones mentioned inevitably drown in the hubris of the action, and so they are left out and the combat is simplified to work with those limits.
All that said, CP won't turnbased. I would hope there'd be a mode (the implied "tactical mode") that emulates it somehow, but that's all there is, a vague hope.
But even with action-heavy realtime FPP combat, there are numerous methods of doing it with "stats" and character agency in mind without sacrificing much of the "action".