What about this ban is anticompetitive? The only think I can think of is accusing them of dumping product (as opposed to price discrimination), in which case the remedy is going to be to making them charge the API price for everything.
In Europe the Digital Services Act (DSA) is beginning to set expectations, particularly for large platforms about not just clear documentation of their terms, but also a meaningful human appeal process with transparency and communication requirements for actions taken.
The DSA is more focused on social networks, but if you were to apply the concepts of the DSA to this story, Google would have violated it several times over.