Some high(low)lights from his Wikipedia page:
In October 2017, leaked emails revealed that Yiannopoulos had repeatedly solicited neo-Nazi and white supremacist figures on the alt-right for feedback and story ideas in his work for the website Breitbart.
Among the figures Yiannopoulos contacted were Curtis Yarvin, a central figure of the neoreactionary movement; Devin Saucier, the editor of the white supremacist magazine American Renaissance; Andrew Auernheimer, the administrator of neo-Nazi website The Daily Stormer; and Baked Alaska, a commentator known for his anti-Semitic and pro-Nazi tweets.
The report also included a video of Yiannopoulos singing "America the Beautiful" at a karaoke bar, where a crowd of neo-Nazis and white supremacists, including Saucier and Richard B. Spencer, cheered him with the Nazi sieg heil salute.
In 2018, Yiannopoulos bragged on Instagram and Facebook that he donated $14.88 to Talia Lavin, a Jewish journalist. In Neo-Nazi and Alt-right circles, 14 represents the Fourteen Words ("We must secure the existence of our people and a future for white children") and 88 is code for Heil Hitler. PayPal and the PayPal-owned Venmo subsequently suspended his account.
I shall judge him by the company he keeps and the views he appropriates, amplifies and promotes.
And that’s all before you get to him inciting violence against journalists, how he feels about Muslims and women, his views on older men being attracted to underage boys. Vile.