Adamantite Chainsaw

A chainsaw keeps cutting for as long as you hold the button, so on a thick tree you never lose time to a swing animation. The cost is reach. You stand closer to whatever you are cutting than an axe would put you, which is awkward when the thing next to the tree is a hardmode enemy.

Stack mining speed from armor, accessories and a good modifier and the swinging tools pull back ahead. With no dedicated harvesting setup, the chainsaw clears faster. If you are building a proper woodcutting loadout, make the Adamantite Waraxe instead. The Titanium Chainsaw is the same tool on the other ore, so there is nothing to weigh up beyond what your world rolled.