If that's the case, then why are there leaderboard's like Hypixel Bedwars? Which is a heavily PvP style game.

Because they were submitted and accepted when the rules were different.

Ah ok. When exactly were the rules changed?

Around a couple years back or so now.

Yeah the game request rules aren't applied retroactively, so there are existing games that don't meet the current rules.

Also, it's likely the game was added by a series moderator, in which case site staff didn't need to approve it.