That has less to do with being fans or not of Killzone and more about being fans of an entirely different genre. Not being a fan of Killzone and being excited for Horizon are not mutual things
Ueda's games all have a similar overall tone, style, and underlying gameplay
Fair point, the Killzone example I used wasn't accurate to what i was arguing.
A better example would be Marvel vs Capcom. Comic book fans who don't care for Street Fighter might get into Marvel because it appeals to them. So my point is even if someone isn't a fan of a studios past work they might get hyped for their next game if it has a wider appeal or different kind of appeal.
Because the Ueda games are similar to each other, if someone who didn't like last two probably won't like this one. All the impressions have indicated that this is one is similar to their past works,