The first movie was profitable and Paul Anderson has no involvement with this sequel.
Also, it must be mentioned that Anderson's concept was the only reason the movie even got made. Fox rejected "close to a hundred" (if you can believe them - I think that's got to be an exaggeration) pitches that took place in the future and involved colonial marines on another planet, because they felt it would be "too much of a rehash." Anderson was apparently the first person to suggest setting it in the Predator-style setting on Earth instead of setting it on another planet, which Fox seemingly adored. So if you have anyone to blame for this, blame Fox for rejecting all the concepts that were based on putting it in "the future."
Honestly, I think the REAL reason why they didn't want to set it in the future is because they were hell-bent on a low budget after Alien 3, Alien Resurrection and Predator 2 all lost money, and putting something in the future means you have to worry about spaceships and futuristic weaponry and crap.
I do think that Anderon's connection between the building of the ancient pyramids and the conspiracy theories about alien involvement and the Predators and using the aliens as training material was pretty damn clever, though.