In all seriousness, this is only going to become worse in the future. Can't wait until the day when smart fridges, toasters and bicycle locks join in on a multi-Tbps attack and break the entire internet.
This really needs to be fixed at the national or international (IANA?) level by mandating the deployment of anti-DDOS source quench and anti-spoofing measures. Any owner of an IP block should be able to register a key and then send source quench messages and this needs to be deployed uniformly.
But I'm not holding my breath. It's like herding cats, and as a general rule nobody anywhere cares about security unless their house is on fire (and then they go back to not caring after the fire is out).
Another thing that needs to be done is to cut off support for this activity. It needs to be made illegal to pay ransom for DDOS or ransomware for that matter. If you get ransomwared or DDOSed that sucks, but that doesn't mean you should be allowed to reward the behavior and finance it being done to others.
Your source quench nonsense sounds like just another piece of pointless infrastructure to be abused.
Because connecting your toaster and fridge over a local network, and running updates via your PC/laptop would be just too complex