Not every game necessarily has to have a respawn or make it a choice to have. In my opinion, not every game should be the same. That is what makes them stand out from the rest.
That's why I mentioned I'm not at all advocating the (future) inclusion of a non respawn option. Though there's one 'problem' with what you say here - the vast majority of multiplayer shooters these days have respawn, all are copying each other. Indeed not all games should be the same, ironic is that if this game had such an option, it would possibly be more unique due to the lack of games with no respawns.
I'm just pointing out that team work and objectives do work when a game doesn't have respawns, and from personal experience I dare even say it works even better. There's more incentive to play as a team when you know you're likely to get punished if you play go out alone and play recklessly. It might promote some more death match based gameplay, but if the design is good, going for the objective isn't rare at all, my examples (Shadowrun and SOCOM) should illustrate that.