Poor decision making in the waning seconds, trying too hard to make passes work rather than go through his progressions, and just generally looking uncomfortable in the pocket. All of this is entirely on him.
That said, I've seen at least 4 interceptions that were not his fault. Two of those bounced off of Robinson's hands; one in the end zone. It's been difficult to watch all around. I've long been an advocate for changing statistical rule regarding INTs. If it hits the receivers hands, shouldn't be charged to the QB. It's more of a negative stat for the receiver IMO.
Not making any excuses for Blake, because he has been playing like garbage, but the above isn't exactly helping his stat line either.