I think 4 out of 10 is a bit nuts, but I have to admit that I found huge chunks of that to be tiresome and not very fun. It didn't come anywhere near capturing my imagination like the original Bioshock did. Heck, I think Bioshock 2 is a better game than Infinite, and that game got tiresome to me too.
The environment in the original Bioshock was just so magical. The environments were varied and interesting. I just didn't get that from Infinite. Infinite felt the same from start to finish, and I agree as well that the Booker was uninteresting, and I just couldn't be bothered to to care about him. I thought the end was pretty much dumb. I thought it was 2001 Space Odyssey (the movie, not the book) levels of incomprehensibility.
That said, I'd still give it a 7 out of 10. It was an interesting enough concept, with decent mechanics and environments, but it was average at best overall.
