Minecraft version: 1.21.5
Modloader: Fabric
Fabric loader version: 0.127.0
Environment: Singleplayer

Mod name: Tree Harvester
Mod version: 1.21.5-9.1

The tree still gets harvested even without sneaking. (I have treeHarvestWithoutSneak set to false.) I have deleted the mod Tree Harvester but for some reason, the mod persists on version 1.21.5. I have tried resetting my profile, deleting the web cache and config, deleting all the mods, yet the issue persists.

I found the issue, the Veinminer mod was conflicting with Tree Harvester