I've argued the Alien invasion film for more than a decade.
The Aliens have been neutered as a threat, the only true victory they have is against Hadley's Hope. Which was less than 200 colonist.
Tell me again why we are supposed to fear them? The fact that they exist in movie after movie and don't ever do anything lessons their mystique. They are scary to the individual, but only barely a threat to the group. Hence every protagonist victory against them.