In all my years, I have only ever encountered 2 people who said they had poor reactions to tea tree oil, as opposed to just using too much and getting a predictable response to overuse.
Even that overuse reaction goes away pretty quickly if attended to. I blame the sellers who don’t include the dropper stopper in the bottle and just allow the product to be poured out like water. One drop goes a long way. Even when using in a bath tub, it is only recommended that ten(10) drops be added to a full bath or small hot tub.