Personally I would prefer that he get out of jail as soon as he is not considered a risk to society, since that is the only valid justification for prisons. Maybe months, probably years. And then he can consider the evilness and futility of his act.
And for all the people celebrating it here, you might consider your own hypocrisy and outright callousness at defending the indefensible. I still can't quite get over my shock at the level of hatred and vituperation here. I thought this community would be better than that.
From a person who knew Luigi Mangione, just published in Unherd:
But while thousands reacted on social media with laughter emojis to Thompson’s murder, I was sickened. Vigilantism is always wrong. If you celebrate someone gunning down a defenceless person in the street, then you advocate for a world in which this is an acceptable thing for anyone to do. You advocate for a world in which a stranger can decide that you’re also a bad person, and gun you down in the street. In such a world, I promise you, your health insurance would cost much more.