It's the wild west phase, after it settles down there will probably be ways to signal you don't want to allow training on your code. But I think it's just like taking your grain of sand from the beach so nobody else can have it. The beach is going to be just the same.
As part of the wild-west phase, it is possible that the inclusion of a single identifiable AGPL project in the training set leads to the licensing of Copilot as AGPL. Such an outcome might lead hastily to the future you imagine.
