Selur mentioned "Avisynth Neo + KTGMC is 7+ times faster than normal Avisynth using QTGMC"
https://forum.videohelp.com/threads/399815-Any-Faster-Way-for-De-interlacing-Using-QTG...e2#post2603492

Two of my PCs have GTX1080Ti GPUs. I couldn't locate much information on the web in English about these programs. Can someone who knows how to use them give instructions on installing and usage? Avisynth script examples would be especially helpful.

I found these pages (not sure what language they're in):
AvisynthNeo-r2827
https://github.com/nekopanda/AviSynthPlus/releases

I downloaded but the instructions are not in English or any Latin language.

KTGMC
Is a Windows 7 or 10 binary available? I wasn't able to locate a link.
https://github.com/nekopanda/AviSynthCUDAFilters/wiki/KTGMC