Fakeyour results show enabling and disabling HPET is functionally the same in regards to frame time.
from what i understand WIndows doesnt use HPET by default anymore anyway and keeping settings at default is best. As regards to input latency im not sure. I personally have seen no difference.
the interval thing seems to change from 0,7 to around 0,02 us, isnt that like the CPU response time or something? probably not that noticeable but i saw screenshots of people with HPET that had way more than that