Consumers don't really care about speed, they care about checkboxes being checked. I'd be surprised if dual core really did anything for getting packets to and from the gateway interface any quicker. If anything I bet it makes it go slower with a naive implementation.
They aren't hacked yet when they make decision about buying the router, and anyway they cannot differentiate based on security promises marketed to them by vendors.
It won't make a difference. Consumers don't care about security on their devices. That is why I quit frankly like things like Bricker bot. The internet is an ecosystem and people's devices should be bricked if they are having a negative effect due to blatant negligence by device manufacturers.
I hope a new round of Bricker bots continue killing devices that are unsupported, incredibly insecure devices. It is a public service (albeit a felony, don't get caught)