Wolf spiders bite afflict poison. Wasp stings afflict venom. The wasp boss has some attacks that afflict poison (lobbed clouds), and others venom (sting). The black widow afflicts both poison and venom at the same time.

Waspidote only removes the poison debuff. So, it doesn't work against... wasps? The current setup is confusing.

Possible solutions:

1) Waspidote should just clear both poison and venom (it's a late game item and costs a lot of resources, anyways).

2) Wasps could afflict poison instead of venom, and then waspidote would only not effect the black widow's venom, and the wasp boss' venomous sting. That would probably still lead to a lot of player confusion (especially during the wasp boss), as there isn't really time to check and see "oh, I've been venom'd not poisoned, of course!". See option 1.

The third (most reasonable) solution is also quite obvious - Waspidote clean venom instead of poison. We already have enough protection against poison when get the Waspidote recipe.