

I assume a lot of the top level staff stick about until their contractually obliged period for getting a massive payday is over, and then look very closely at whether they actually want to be told what to do by a bunch of suits all day long.
Realistically they’re working to make somebody else richer at that point, and there’s only so much enthusiasm anyone can have for that. Certainly not enough for the long hours needed in the games industry.
The first few were really good on console. I played the first one on PC as well and there was definitely something missing with mouse and keyboard controls. The vehicles especially.
You have to remember that most FPS on consoles were pretty terrible back then (e.g. Medal of Honor series), and there was a lot of experimentation to try and find a control scheme that didn’t completely suck, along with just the right amount of aim assist. Other devs were still wrestling with that into the Xbox 360 era. Sony put so much effort and money into Killzone, and it wasn’t anywhere near as good as Halo.
Plus, split screen co-op made it very popular. It’s one of the few games to keep that into the modern era as well.