Well stomps is subjective and maybe a slight exaggeration but I would say gears 5 is an easy win for the 1080ti and again that extra 3gb of ram. If you are not concerned with raytracing the 1080ti is the better card imo..... Certainly not worth "upgrading" to (again imo)
That link has the 2080 10% faster than a 1080ti. I question that as well
The simple truth is that they are about equal in performance. The only difference is that Nvidia will continue to optimise for the 2070 Super and not the 1080Ti. So the going forward the 2070 Super will improve but the 1080Ti won't.
Within a few driver releases the 2070 Super will be as fast or faster than the 1080Ti in Gears of War 5.
The 2070 Super is faster in VR.
The 1080TI is a great card, but, unless you are getting one a lot cheaper, the 2070 Super is a better buy at this stage. Even if you have no interest in RTX, it's still a better buy.
Where does the link I posted have the 2080 as 10% faster than the 2080Ti?