You gotta give something in exchange. It's not a free gift - it's a contract, where both parties give something. WotC gives this powerful brand name, in exchange for which you give up certain rights. You're not forced to sign that contract; but if you think it's worth it to you, you will.
And I refuse to give control of the English language to WotC, or conform to their ideals of what my IP should be. They control their IP, not mine. They are asking WAY too much for those names and things that are in public domain.
Fortunately, the wealth of legal jurisdiction disagrees with you. A contract is legal as long as it doesn't require any criminal act.
This will only be proven true AFTER the GSL has be involved in a court case.
You're free to do all that. You just don't get to slap a shiny D&D logo on your product. I'm a pubisher with a vested financial interest in this, and I think that's perfectly fair.
The thing is you don't have to have a financial interest, it just happens that you do. I could not create a fan product with the D&D logo because it tells me what I have to use as definitions for public domain terms. That is where the thing falls flat.
What you should be giving up is the right to create your own game based on the IP of WotC, that the OGL allowed; but not your right to create anything else for the game just because WotC wants to circumvent your rights to those public domain terms.
How much actual control of those public domain terms do you give up? What rights do you retain for other things in regards to those public domain terms?
What you have below is a little part of that, but other than the OGL, are you giving up your rights to use those public domain terms in other things just because you have signed this GSL?
The only thing stopping me signing it is the "trash all your OGL stuff" clause. Can't afford to do that.
That just makes me want to kick someone in the nuts! You are rightfully so to be offended by that section because it is a slap in the face not only to publishers, but consumers as well.
All hail WotC gods of all gaming and bow to their whims.

It just makes me want to listen to the convention meeting where someone recorded the closed session between WotC and 3PP discussing the OGL/STL and what was coming and the things Bill S. said and got mad at the 3PP because they didn't just blindly accept WotC telling them what to think.
I don't recall a pleasant thing said on either side from that meeting, but seemed everyone left unhappy. Wish I knew if I still had that or where to find it again!