Should I get a 1080 Ti, 1080 or RTX 2080?

The new GeForce generation offers almost 1.5 times more performance and allows free gameplay (over 60 frames per second) in 4K resolution and with HDR enabled. It should also be noted that titles using technology related to machine learning and artificial intelligence (Deep Learning Super-Sampling) "accelerated" even more.
However, some of these new technologies are not yet fully elaborated, as evidenced by, for example, the unfulfilled performance in Shadow of the Tomb Raider.