The crux of this issue is that a person may not be deprived of life, liberty (rights), or property, without due process of law.
A felon is denied life (in capital cases), liberty (freedom, while in jail, and other rights such as voting, choice of residence, and so on, upon release) and property (fines, forfeitures), WITH due process of law.
So it's arguable that denying felons the right to own firearms after their release is within the scope of the police power, but I wouldn't be surprised to see a lawsuit come up where a non-violent felon who has completed sentence, parole, and all other supervision sues for his right to armed self-defense.
A felon is legitimately made a slave of the state, as permitted in the Thirteenth Amendment. The Second Amendment never applied to slaves. Of course, some people think the public at large should be slaves of the government--hence the need for disarmament.
I have known a few people in my life who should NOT have a gun. Because they will get all drunked up and start a fight and pull it out and shoot someone. I honestly don't know how to write the legislation on something like that. I sure as hell don't want Schumer and Kennedy deciding who is dangerous or not.
As the wise Chinese proverb says, "may you live in interesting times".