Don't the telecoms companies make huge profits on roaming fees? Would this then mean that the companies would be pushing against this move?
Of course, the roaming fees /outside/ Europe are now eye-watering.
They'll continue to charge roaming fees anyway, right up until they lose a lawsuit over it. Why would they do anything else?
Remember that the EU was "born" with the main objective of creating a "single market" through the standardisation of laws across all member states.
FWIW MVNO (operators with no physical network and leasing network time) are already very common in the EU.
Still, there is some lobby going on in the EU which wants to detach operators from the network, and make the network independent from everybody. NetCo + OpCo != TelCo.
I really hope this last scenario happens. But it's a bit of a utopia.