It’s not like there are mustache-twirling villains coming up with ways to punch down even harder here. Diets high in sugar are more likely to lead to painful and even dangerous oral health issues, pancreatic/kidney/liver issues, diabetes, and obesity with all of its knock on effects.
It only has a negative effect for people who will never reduce the sugar in their diet, and those are the people who should be paying into socialized healthcare at a higher rate because they’ll need lots of benefits later. So really they’re saving to take care of themselves, making this a net positive long term.
I know it’s harder than “just stop eating sugar” but feelings or preferences don’t change the facts of biochemistry. Until you can disprove the findings, the policy should reflect the state of the science.
And by all means find more/better ways to incentivize or even subsidize healthier options for those on the low end of the socioeconomic ladder. That is absolutely one of the things taxes like this should fund.