There's really no point. A few high sensitivity assets are lower resolution, but any state actor that wants very high resolution shots of military facilities already has it and on a quicker update cadence than google maps allows.
This isn’t an answer to your inflammatory question, but there are only a handful of nation states with nuclear weapons, and France is one of them.
These aren’t hand-me-down US warheads on the back of a missile truck: the flagship of the French navy is a 40,000 tonne nuclear armed, nuclear powered aircraft carrier floating above a strategic submarine fleet that can destroy the world.
Are we talking about the same France? France, one of Europes largest military powers which actually use their military in various conflicts around the globe?
Maybe their argument is that France has nothing to fear from anyone, so why the secrecy? Of course it's nonsense no matter how you spin it. All militaries love secrecy (except maybe the ones that are just for show, but I expect even the Swiss Guard in the Vatican has its secrets).
Someone correct me if I'm wrong, but I don't think the biggest threat to domestic military facilities are foreign state actors but rather domestic terrorists, and those usually don't have access to any military-grade satellites.
Interesting that you mention only domestic military facilities... When I was deployed to Afghanistan ten years ago, with rockets and mortar rounds landing daily inside the perimeter of our Forward Operating Base, I was irritated to see recent and high-resolution satellite imagery on Google Maps. I can see my sleeping tent, office building(s), and parked helicopters in perfect clarity. The imagery hasn't been updated since then, so you can still see everything despite this base being abandoned years ago.
https://www.google.com/maps/@33.9428134,69.0629605,492m/data...
Do they need military-grade imagery? The Chinese or Russian militaries do because they’re trying to estimate war-time performance but I find it hard to believe that there are any domestic terrorists building sensor arrays to support SAM batteries. If they’re trying to blow one up, the resolution on a consumer drone or telescope would likely be more than enough.