Yes and no.
For missions, yes. We should make the environment highly dynamic. I'm reminded of one of the later games (Nightfire?) that featured "Bond moves" when the player noticed a highly theatrical way to accomplish a goal. I'm not necessarily into devising specific ways to do things, but yeah...the player should be able to think of ways to deal with problems and see them work. Use laser-watch on a seemingly meaningless floor grate to weaken it, guard walks over it, it breaks and he falls to his demise. Shoot a cable on the ceiling to make it drop down, attach to a door knob, if a guard opens the door he gets fried. If we're going to make Single Player matter, it needs to capture more than the gun-play of the films. My spitballs here are probably implausible, but you get what I'm talking about.
For multiplayer, maps need to be static. Except for the grand dream of a map that automatically opens up when players pack in and locks away paths when players leave, there is really no opportunity for any grand interaction that isn't going to either be annoying or one-shot. Exploding barrels are accepted as cliche, because they are point traps that just make an area more-dangerous unless you pop them before you go in, or pop them when someone tries to sneak by them. Once "used" the trap resets. But, you can't do that with big things like collapsing a staircase (which also chokes flow, which is bad for multiplayer) or destroying walls. (We already had problems with glass respawning on people and trapping them in place.)
Indeed, the barrel is your guide for making a proper map trap. It's easily defused (with a drawback, you can't use it and everyone heard you do it) and anyone who is close enough to be killed by it knows he's risking himself by going near it (usually for a power item), it doesn't break any other feature of the map, and it doesn't break immersion when it resets. You can camp it hoping to get a cheap kill on someone, but it isn't a winning strategy. Yet, every once in a while in a gunfight, barrels make the difference. Caves' generators are barrel traps in the exact same vein, and work well.
