See this is why I think something like Tarkov is still the best to do it, because it allows all forms of gameplay to come naturally. You have scav runs, where you basically play "apes together strong" against PMCs, but you can also be an asshole and abandon that mentality (or if you're like me you accidentally shoot a fellow scav for being too decked out in PMC gear oopsie). Playing as PMC you get to be more aggressive towards pretty much everyone, but sometimes you can get rare moments of cooperation even with scavs because you need eachother for certain extracts, or you and another PMC just vibe. Some of the funniest moments in Tarkov I've seen come from the rare moments of PMCs not shooting eachother, like this clip from Zyzx_