Well, they are. Total Recall, Running Man et al are better suited to the kind of role that Arnie was so good at, as the looser rules of science fact vs. science fiction are more open to be played with. Running Man's oppressive government control of the population and Total Recall's oppressive control of a whole planet allow for greater flexibility in terms of both plot devices, and avenues to be explored both physically within the film and as metaphors within them.
By contrast, films like Commando and Red Heat, both modern day action films, are lacking by their nature - the characters are limited to running, fighting and occasionally driving fast. But within the setting of The Now, the films lack both the scope of the dystopian, and also the opportunity to pursue more fanciful scenarios.
Some films, however, marry the two aspects perfectly. The Terminator series, which itself could be interpreted as some of his finest work, is a modern day dystopia, a foreboding snapshot of the future. The marriage of modern day elements with future happenings (the Terminator himself) allows a blurring of the lines between the standard car chases etc with phallic arm cannons and melting men.
Perhaps the most standout example of crossover work is Predator - in many people's opinions the best Schwarzenegger film. The modern day setting, blended with sci fi elements is both enrapturing and well played out.
However, it must be said, this could lend itself as much to the fact that the modern day setting is so far removed from an urban environment as to render it inert, and thus the modern day setting standpoint becomes null and void.
Overall, whilst a good balance of Arnie films appear in both the modern day and future dystopian settings, it is my opinion that dystopia wins hands down. Not least because the guns are a lot better.
