From your description, it sounds like the title might be missing the word “living” or “standing”

@JimHays Is there a taller dead tree?

@IsaacKing If Hyperion is chopped down, some might still call it the tallest known tree.

@JimHays There are unsubstantiated claims of older trees, also: https://en.m.wikipedia.org/wiki/List_of_tallest_trees#:~:text=Other%20researchers%20have%20developed%20models,%2C%20a%20126%2Dmeter%20tree.

@JimHays Edited description to clarify I'm counting distance from the ground, not length of the trunk.