Human Revolution was one of my favorite games of the last decade, I was totally drawn into the aesthetics, the story, the music (that soundtrack helped jumpstart my interest in electronic music), the fever dream "what if every early 2000s conspiracy theory was real?" setting, and the Splinter Cell style stealth gameplay.
Mankind divided was disappointing in many ways, but still had its moments. I remember when they made an iOS mobile game to tie in with MD's imminent launch and it had a "Deus Ex Universe" title card, implying that there were ambitions to widen the series beyond the main games.
This really blows. It's another example of how the AAA game industry has deteriorated over the last decade.