An ad for the Duo subscription pops up every time I open a Proton service like mail or pass that blocks the entire screen and I have to manually dismiss before I can actually do what I logged in to do. I am already paying for unlimited and neither need nor want Duo. The overlap between people who don't like ads and people who pay for the privacy that Proton provides is pretty significant- this a tactic that is likely to drive myself and others away from your company.