Did the government force them to sell their electricity to other EVs? AFAIK the CCS connector is forced which had been shipping for a while. Allowing other EVs to charge seems to be business choice.
"The right to build a charger comes with responsibility to service electricity to any EV car."
The EU, and in particularly Germany, is strongly nudging Tesla that, if they do it now, then right now at least they can do it in their own terms, and existing experience can flow into legislation.
If they wait, then they will need to complain with whatever is legislated, and without any experience, they won't have a seat at the table (while other EV charger systems with experience will).