I feel like I'm repeating myself but once again the "do your own Research" crowd didn't do its research. I'm guessing you didn't read the study and just repeated the misinterpretation somebody made about it, like thousands others did. The study does not compare the vaccinated with the unvaccinated, but the delta variant with the older strains. It says so right in the abstract: "Viral loads of breakthrough Delta variant infection cases were 251 times higher than those of cases infected with old strains detected between March-April 2020"
So, it simply confirms what we've known for weeks: with the delta variant, viral load peaks can be high even for vaccinated people, but not higher than the unvaccinated like your click-bait title suggests.