Antitrust legislation is reactionary, so no. The idea that small production is inherently better is a bizarre petty bourgeois affectation that ignores the economies of scale and general gains yielded from larger, more complex industrial arrangements.
Encouraging "small production" is unequivocally not the purpose of anti-trust laws. But, I guess if you're a marxist, you're relieved of the obligation to pay attention to reality. "Petty bourgeois!!!" "Industrial arrangements!!!" Great economic analysis.
The point of anti-trust laws is to prevent monopolistic behavior that restrains competition in the market. I guess marxists need to dislike that idea because they want a government monopoly instead of a free market system, but that's the idea, like it or not.
I think it's an unlettered, silly thing to across the board say large corporations should be broken up. There's nothing necessarily wrong with a large corporation. But, there are probably some candidates for antitrust action that we should think about, big banks, telecom, etc. Unfortunately, we won't because of money in politics. Oh well.