If both oriento and https://www.svp-team.com/forum/viewtopic.php?id=7530 mentioned a sudden performance drop compared to previously
it could mean that one of the recent SVP updates like updating python version or one of the recent hotfixes increase the processing power required for live interpolation just above their system's capabilities
but we don't have a downgrade SVP button to let them investigate 
best scenario would be if devs try to interpolate a video on one of their machines at high enough processing power that they can reproduce their issue, but not too high so rollbacking a couple of SVP updates would see a noticeable performance improvement
this means devs should go through "A few weeks ago..." of SVP changes in order to confirm if slowdown is related to a critical component that requires updates or not to conclude if it's fixable or if we should just blame Nvidia's latest drivers
offtopic question:
this looks promising and uses RIFE and Vapoursynth, would it be possible to integrate on top of SVP with a checkbox?
https://github.com/routineLife1/VS-DRBA
https://github.com/routineLife1/DRBA
or probably not worth it