I'll agree with him, though I'll take a different tack: I believe people who are institutionalized--whether criminally or civilly--ought to be denied arms. I believe violent felons and people whose mental issues are bad enough that they're a danger to others ought to be institutionalized until they're no longer dangerous.
Free people should be, well, free.
To a degree I agree with you. The problem is funding, especially on the mental health side.