So the suggestion here is to implement source routing on a whim, with a table of 100+k entries? At your peering point?
An ISP has to do what it has to do to save their business when a large attack hurts their business. This may be what the attacker wants but that's not an excuse to do nothing.
But what machine learning has to do with this is not clear. Null routing protects you against traffic volume. Machine learning sounds like it maybe can help diagnose more sophisticated low-volume attacks. Maybe. You don't want anything remotely compute intensive when mitigating attacks.
An ISP has to do what it has to do to save their business when a large attack hurts their business. This may be what the attacker wants but that's not an excuse to do nothing.
But what machine learning has to do with this is not clear. Null routing protects you against traffic volume. Machine learning sounds like it maybe can help diagnose more sophisticated low-volume attacks. Maybe. You don't want anything remotely compute intensive when mitigating attacks.