Home users reconfiguring routers would not really resolve the issue, but yes, egress filtering would be effective in theory. Unfortunately that's a maintenance nightmare and costly and there's no incentive to do it.
Besides closing down open resolvers, the real solution to this particular DDoS lies in the DNS protocol. The attack's practicality comes from RFC 2671. If that were amended to either return the maximum size of a packet to 512 bytes for UDP packets (but allow TCP packets to be any size), there would be no benefit at all to this attack. For existing resolvers this would require either DNS services being upgraded or firewall rules being put in place to limit UDP packets on port 53 to 512 bytes.
Shutting down open resolvers is about as much work, but unfortunately still leaves the attack possible because it's inherent to the protocol.
Besides closing down open resolvers, the real solution to this particular DDoS lies in the DNS protocol. The attack's practicality comes from RFC 2671. If that were amended to either return the maximum size of a packet to 512 bytes for UDP packets (but allow TCP packets to be any size), there would be no benefit at all to this attack. For existing resolvers this would require either DNS services being upgraded or firewall rules being put in place to limit UDP packets on port 53 to 512 bytes.
Shutting down open resolvers is about as much work, but unfortunately still leaves the attack possible because it's inherent to the protocol.