A 1080Ti + Nvidia Image Scaling, you are sorted for quite a while even at 1440p...dare I say with some settings pared back even 4K.
Pretty much anyone with a 1070 or higher doesnt need to be panicking about the GPU prices just yet.
Just play on high or medium turning down those settings that eat frames for free.
And if you were one of those hyper enthusiasts who always gets the xx80+ chances are money wasnt "really" an object to begin with.
And once UE5 and other Temporal upscaling/Injection techniques are more prevalent our pascal and turing GPUs should last quite a while.
Even games that favor AMD hardware you can use Nvidia Image Scaling to upscale to a 4K resolution with a few settings dropped.