What is this “minimal bloatware” of Mint exactly?

I don’t know Arch or your DE, but purple is your OS’s accent color. perhaps the issue is not in qt5 but somewhere else like /usr/share/themes, ~/.themes or ~/.local/share/themes.

(sorry, english is not my first language) what does it means “negatively politically oriented”?

the composite last names of both the italians is typical of ancient, rich and maybe noble families, so at least for them it might be money.

I think this is how The Last of Us begins.