That's not how that works. You're welcome to compete by making a different RTS game, but you can't just copy theirs and offer it up for free and then say they should "outcompete" you.

It doesn't matter how the market should behave (I agree with you about free competition), the reality is that Blizzard owns the trademark and there are legal processes surrounding that.

They can compete, just not with the same trademarked name or, as previously, copyrighted materials. I'm not referring to how things should work, rather how they actually work.