If a country were in your individual position, I'd definitely call that self-sovereign, but I don't think that's how "80% self-sufficient" would actually look like. (I don't think that 20% of most countries' consumption is entirely discretionary, for one thing, whether measured by peak or average load.)
At >95%, it's probably a very different story. At that point, you basically turn off your aluminium smelter and you're good :) (And note how GP said "renewables", which gas isn't.)
And my point really isn't about oil specifically, it's about GPs "renewables increase sovereignty" thesis in general.