That's already what happens, that's why it's so expensive. You usually have an all included costs on one side and whatever minimum the private company could get away with legally on the other side.
The French gas plants got built to smooth out renewables, there's only a single gas plant built before 2010 and it wasn't even connected to the pipelines, it was a factory gas reuse.
I do think it was an environmental and diplomatic (as seen now in the Russian war) mistake.
