Here is what Stallman actually said about his motivations for GNU.
His statements don't seem at all anti-capitalist in bent, but very pro-freedom, and fully intending to promote the intention of the Founders in increasing human knowledge through LIMITED patent and copyright rights. The man is unquestionably utopian in bent, but I don't see him as intending an end to capitalism through GNU at all, just moving to the idea of a "post-scarcity world." And even were his aims anti-capitalist, he will not end capitalism simply throught distribution of free software.