Go ahead.

No kidding, I mean it's not smart  to make predictions like this at this point but can this game sell over 5 million copies? I'd say it definitely has the potential.

That mathias programmer got his metaphores mixed up.

He basically said:
"what your seeing here is just like a tiny bit of the foot of the iceberg"
but he was trying to say there is much more to the game, than we ve seen so far.

Hes buddy response by going "we should go back now, and work on more" (although with a smile on his face)
Another thing I noticed was both of them mentioned not being allowed to talk to anyone about the game project, and where worried what their friends might think of it ect.

Mathias sounded like he wanted his friends to be proud of his work, you can tell these guys put everything into makeing this game great.

Thats a healthy thing, a game developer that is no longer excited for the work he does, is only going end up disappointing people.

It's happen on every generation, trust me. When i am on 7th gen, a lot of people saying the same thing "no noticeable difference this gen from last"

Do I HAVE to play as a woman in this game?

I believe this game will end up being more than 5million copies sold.

yeah it might be to early, but the games really different from the rest of SONY IP and also it looks bizare and majestic at the same time.

They said the main character is a woman the one on the footage. But maybe they will add some companion, or other choice i dont know, the game it self still on alpha build. 

IGN: 5/10 ... Too much robots and too good of a strong non-sexualised female protagonist.

Hey, here is some more info for the OP. Including some cool stuff on that giant robo-rex!

http://www.engadget.com/2015/06/17/horizon-zero-dawn-first-demo/

I hope they give you at least a choice to play as a male character especially since this is an RPG.