It's not the Hershey's chocolate bar that this impacts, and makes it taste of vomit, as already mentioned it's the soured milk that causes that. The extra vegetable oils impact the white chocolate more obviously.
Have you tried American white chocolate, like the white Kisses? Candles have more flavour.
My grandparents used to have a fruit bowl that looked extremely tempting. However there were not real fruit, and even though I was a child, that waxy tasteless mouthful of disappointment has never left me.
My MIL has white chocolate kisses (and those grim white chocolate mint ones) every Christmas, and they remind me of that same day if I ever feel like I might have been too hard on them and try one.
Candles might have dripped melted wax on some birthday cakes, in my past...
(( But even so, I can't say any kind of white chocolate tastes like or has less taste than candle wax. White chocolate has distinctive tastes...which I don't like, and stubbornly refuse to believe the tosh that it's chocolate. ))
Have you tried American white chocolate, like the white Kisses? Candles have more flavour.