First of all, never get your mythology from Youtube comments.
Second, the second comment is the accurate one. Χ in Greek is transliterated as _ch_ , and that's where we get our time words from (as they mention).
I believe the first comment is just confused, where the user once read what the second person is saying, but got it exactly backwards. In both cases they're right in saying that originally _Chronus_ and _Cronus_ (or Khronos and Kronos, Greek Χρόνος and Κρόνος, "Time" and "Father of Zeus") weren't the same. The first person got it backwards, and the second one got it right.