Duolingo has enshittified so much over the last few years.
Even if I had the ability to become a millionaire tech founder, I don't think I'd want to because every "I want to make learning new languages free and easy for everyone" becomes a "I have to drive 3% more ad revenue this quarter by charting my users' every bowel movement".
I suspect the reality of being a rich tech bro is watching your adult self slowly consume your own childhood dreams, aspirations, and soul.