$175,000 for 50 years? He's 71 now so he went into prison at 21. That means he spent virtually his entire life in prison. He could have done so many things, but instead he needed to sit in a prison cell. All because he was wrongly convicted.
And because I'm a math geek and need to figure this stuff out, $175,000 over 50 years is $3,500 a year. If we calculate what he would have earned at the federal minimum wage over that time frame (ignoring bank account interest or inflation just to keep things simple), we'd get over $500,000.
They're giving him a third of what he should have earned at bare minimum. (And that ignores all the other horrible things involved with being wrongfully imprisoned for 50 years.)
My guess (also not a lawyer) is to render the verdict as appeal proof as possible. If he wasn't allowed to speak, he would have claimed that his rights were violated and if he had been allowed to give the closing remarks himself, he would have been found totally Innocent.
Engoron let him talk relatively briefly, cut him off when it was clear he wasn't staying on topic, and closed off this appeal argument.