It was not for nothing that Salazar Slytherin hid his brainchild so carefully in a secret basement; he was a seer. For for Magic, first of all, there is only one Law: children are inviolable! And only then - everything else.

So. Tom Riddle did NOT kill Moaning Myrtle, did NOT create any horcruxes, well, they didn’t let him do it, they didn’t let him! And on top of that, the awakened basilisk took the post of director. And I have nothing to do with it, it was the naive grandfather Dumbledore who knew nothing about the saying: “don’t wake up the trouble while it’s quiet.”

Author’s notes: I decided to fantasize on topic: “how would history have gone if Tom Riddle had not been allowed to kill anyone and create horcruxes”?