@easyrider The serious answer is that it's always a moving target.
The 2080 will be phased out for the 2080 S which will then be the start of the high-end in my estimation.
The 2070 S doesn't get to be high-end*, because it's not based on absolute performance, but what's above and below it.
Otherwise, the low-end would still be the low-end from 2000~, or whenever the first proper GPUs came on.
As stuff gets older it goes from being high-end to mid-range to low-end to being used to prop the shed door open.
For the time being I would suggest the 2080 is still high end, and *if the 2070S really does match it, then it gets to be high-end for a short time. When the 2080 S comes out, the 2070 S drops back into the mid-range.
This is all just my opinion, of course.
Maybe some people will see the 2070 S as high end. And maybe they're right.
I will not even consider the possibility of the 2060 S being high end tho! That way lies madness!