That is the spiel from academics on the publish or perish treadmill. Fossil burrows of the same form as the European worms exist in North America. Worms were also maintained to the south of the ice cover so it is disingenuous to declare that all North American worms are nonnative.
Pressure to publish = dismiss any academic claim without evidence? No
> it is disingenuous to declare that all North American worms are nonnative.
Nobody made that claim. That's the strawman you chose to argue against instead.