Who is he
The guy responsible for giving bitcoin its worth. Without him, we'd be trading in double digits now.
How do you get to that? He is actually the opposite of what you saying.... without him we would have been trading in quadruple digits by now. The amount of damage Mt Gox caused the reputation of Bitcoin,
Surely it was the only game in town for many years. Maybe somewhere else would've opened up but there wouldn't have been any type of economy without it. If only he'd shut down when he was still ahead.
Mt. Gox certainly damaged Bitcoin, regardless of whether or not it was the first exchange to technically exist. It should have been treated way better and there should have been some professionalism with the collapse instead of the BS we see today.
The thing is, Mt. Gox shouldn't have shut down when it was ahead either, because that would have likely been detrimental as well, but maybe less so than the collapse of the exhange.