Some people, though pretty loud ones say Halo 4 ruined the franchise. The same ones say MP sucked and no one wants to play it. But Halo 4 isn't only still played on Xbox 360, Halo levels are often chosen by MCC players. Isn't that a bit strange if no one likes it?
About microtransactions: You don't need to pay money. And actually warzone is the only game mode where you need REQ's at all. That's actually much ado about nothing.
On the other hand there's the campaign. In some ways it's more typical Halo than Halo 4 was. In others it's not. I'm not saying it's perfect. The campaign is good but not great because of multiple reasons. But complaining about everything is outright stupid. There's enough to criticize, but not to complain about everything.
And yes, splitscreen. That one really is an issue. Because splitscreen MP and coop always was somewhat of a Halo gold standard.