Post in question for those wondering: https://boards.na.leagueoflegends.com/en/c/gameplay-balance/ApIZIVkn-lol-riots-reason-for-gutting-all-the-tanks-champions-is-because-they-are-low-lethality-for-lcs
Correction in question for those wondering:
[{quoted}](name=Academy Kayn,realm=NA,application-id=3ErqAdtq,discussion-id=ApIZIVkn,comment-id=000b,timestamp=2019-10-05T09:04:39.616+0000)
Assuming this is what you're going off of, you're completely misinterpreting the context of it. When they say low-lethality, they don't mean "people who have low kill potential", because their example is Tahm Kench, a tank whose had no issue killing folk these last few patches. They're talking about Low lethality in terms of "They actively stop plays too easily", leading to points where mistakes can't be punished. Once again, Tahm Kench is the example here, a champion whose been an issue in the past due to too easily negating plays and picks with his Devour.
Worlds is a spectacle event, no one wants to spend hours watching nothing happen, and then one fight decides the game. Riot's quote isn't even saying "Low Lethality champions", it specifically says "Low Lethality Metas", meaning, games where nothing happens. Tanks are anything but low lethality, because they are active play makers, making picks and engaging fights. They are everything that Riot wants with worlds, people actively picking fights.
What Riot doesn't want, are games where nothing happens, because no ones mistakes can be punished.