Yes, hollow points are completely legal in I believe all 50 states. Hollow points and soft points are the preferred for self-defense and hunting because they're far more likely to expand and make a larger wound more likely to drop the target with the shock, rather than having them acting completely normal for the 10 or 15 seconds it takes to kill you and dropping dead.
Hell, a lot of states make armor-piercing rounds and far more exotic ones like incendiary and explosive legal. There's all kinds of ammunition, and I don't think any are banned by federal law.
As for this video, I can't say I approve even slightly of his actions. Publicly complaining about your parents is NOT some kind of heinous behavior that deserves strict punishment, and considering that this is the kind of man to react to his daughter complaining by publicly humiliating her and shooting her laptop, I don't think that the house is one where dad is a saint trying to deal with a bitch of a daughter.
The shooting is where it just gets nasty. Let's not discuss whether or not he was allowed to shoot the laptop and whether or not paying for something means you can destroy it after giving it to another person.
What I WILL criticize is that he's shooting a hard plastic target from a few feet with no eye protection and presumably no hearing protection; the latter is unwise and the former is very unsafe. He's also firing a live weapon next to his house, as well as within view of a busy road and other households. There's good reasons that all three of these things are illegal, most of them relating to the fact that one slip can result in someone getting a surprise .45 ACP visitor.
I refuse to put my faith in a man who demonstrates such dangerous retribution and has the audacity to brag about it to millions.