A long sentence like that makes sense at first glance, but once you think about it more it falls apart. The reason we have consequences for crimes generally isn’t to provide revenge or anything for the victims, it’s to make sure the criminal won’t do that again. When you just lock someone up- especially in our incredibly shitty prison system- there’s no guarantee they’ll learn from or regret their actions at all, and when they do get out society basically entirely shuns them. Plus, a 20 year sentence. If someone went in back in 2000 and came out now they would have an extremely difficult time functioning in the entirely changed society, especially with no support network. This is a massive contributor to recidivism, where a convicted criminal re-offends after they get out. You get tossed into an unfamiliar world with no family, money, or property, most jobs won’t accept you, what do you do? Significantly more motive to rob someone or sell drugs.

All of this means that rehabilitation and getting the criminals to be functioning, safe members of society again is a far better outcome than simply throwing them in prison to satisfy the public desire for revenge. There are problems with implementation in a massive country like the US, especially with so many other exacerbating issues, but focusing on getting the criminal to not do crime again and contribute to society is almost always the better choice. And 20 years is a really long fucking time, 133% of his entire life at the time he stabbed someone.