In the AVP Requiem ending, the military nukes Gunnison, which kills both the Predator and the hybrid creature, and the survivors live because troops find them after the helicopter crash. Dallas, Ricky, Kelly and Molly all get out, but the town does not.
The last scene is the one that matters for the larger saga. Colonel Stevens hands the Predator's plasma pistol, the weapon Dallas took during the hospital fight, over to Ms. Yutani, a representative of the Yutani corporation. In my opinion, that handoff is the real final beat of the film, because it says the weapon will be studied rather than buried. A synthetic made by the Weyland-Yutani corporation, Thia, appears in Predator: Badlands (2025), so it could be argued that Requiem planted a thread the series later picked up again.
As for the creature fight, the hybrid and the Predator fatally wound each other below the helicopter, so neither wins. I would call that the film's most honest choice, since the Predalien had already wiped out the crew of the Predator ship in the opening. Perhaps the title is the point: a requiem is a mass for the dead, and by the credits there is a lot of Colorado to mourn.
The nuclear strike also separates Requiem from the other films where a Predator hunts humans. In Predator (1987), Dutch Schaefer's team is whittled down in a jungle, and the cost is a squad. In Predator 2, the Los Angeles heat wave and a federal task force led by Peter Keyes give the military a seat at the table, but the city survives. Requiem pushes the same idea further, with Colonel Stevens ordering the destruction of a whole town to contain the outbreak, so the human cost is a community rather than a unit.
The set pieces show the same escalation. The school pool attack, the blackout caused by the Predator's weapon fire at the power plant and the hive in the hospital all happen in places where ordinary people live, which is a different fear from the Antarctic expedition of the first crossover. The Brothers Strause came from visual effects at Hydraulx, according to Variety, and it is fair to read the finale, with a helicopter dropping out of a mushroom cloud sky, as the work of directors thinking in spectacle first. That being said, the Yutani handoff gives the spectacle a point, and it is the one moment where Requiem looks beyond its own town.