I'm not sure my position on 2A but it seems you're making a pretty big leap to connect them.

Guns kill others. To me, that's a big difference. Gambling does not, only indirectly, you gamble your money away your family doesn't eat. But if you're going indirect than anything fits. Cars kill more than guns.

You could argue the similarity is that some people can be responsible with guns and others can't but you're back the previous point. Irresponsible gun use directly harms others. Irresponsible gambling at most indirectly harms others.

> Cars kill more than guns.

In most countries, but not in the US.