How does acknowledging that they were gay or bi "diminish their accomplishments" in any way? You're presuming that being LGBT is a bad thing. And I did in fact already know that Roosevelt and da Vinci and some of the others were gay, but I know that many other people don't know that. What's the harm in informing people about it? Why does this information need to be concealed or censored? No one is forcing you to read this, so if you'd rather not know about their sexuality, just go and read something that is more up your alley.