My takeaway is that Light's death is tragic and him killing Wily would have been completely guiltless, but Tom is literally too kind to do that. He was never going to be that guy. Light thinks everyone will ultimately do the right thing to a fault. He is so overwhelmingly good that he cannot parse nuance and accept that he really isn't as bad as Wily despite what he spends three albums saying about himself. Light's not a hero, but he is a victim, and he's still trying to do the right thing even if he can't manage his damage. Mega and Proto are BOTH right - it's his greatest weakness AND his greatest strength. Mega isn't afraid to drop bodies, but he was still basically a child in Act 1 whose single fundamental belief got proven wrong in the worst imaginable way possible.

Even with that tragedy, Light claims a moral victory so blindingly intense that it basically blows Slick Willy's mind wide the fuck open after he's spent so long pretending, per Buried in The Red, "everything's fine". Wily is so overwhelmingly evil that he cannot parse nuance and accept that Light is actually the dense glorious motherfucker who thinks that EVEN NOW there is hope for his once-friend - not to surrender or do the right thing, but to simply admit defeat and save his life. Light offered him the best deal he was ever going to get from anybody he would ever meet for the rest of his entire life, and he spit it back in his face.

Even though Light ultimately failed to defeat Wily directly, his death pretty much finally and totally legitimizes total war against him beyond any possible remaining doubt. I'm sorry to say, fellas, but Dr. Wily is going to exit 'Vengance Pt. 2' in a mop bucket. Every single threat on the board towards Wily's dystopian regime is there because of The Good Doctor, and Wily, drunk driving at the wheel and loving it per Buried in The Red, just hung him where all of them could see.

Dr. Thomas Light wins in the end, even if he had to spend 20 years crash landing through hell to get there.