I'm kind of joking of course, if they have two teams and want to make a different game then that's fine. I would rather they had a heavier focus on horizon than do that though.I think it's best what they are doing. Wouldn't want two teams to be dedicated to making Horizon games. They'd probably get stale that way.
A new IP would be excellent.
Also Killzone is kind of dead, I'm not sure it could ever sell well.To be honest, I don't think it's very meaningful to look back at the Killzone sales.
Naughty Dog exploded from Uncharted 1 to 4. The first game sold a fraction of what the 4th one did. And it took years to get there. In the end it became a billion dollar franchise, but at the start it wasn't much bigger than Killzone.
SIE as a whole has blown up in the past 6 years or so.
I bet if a good Killzone game came out today, it'd sell double what Shadow Fall did.