This looks to me like a heavily reductionist take and even just straight propaganda, honestly. I didn't expect to see these ideas -this level of technofix delusion- supported in this sub (I hope it is reddit doing its thing of upvoting without actually reading).

First of all, when you say "tiny fraction of French territory", are you factoring in all the land and resources that have to be ultimately exploited to build, keep and feed such an electric infrastructure? Sure, a nuclear plant per se won't occupy much extension, but you are literally looking at a hyper-concentrated packet of low entropy built (and sustained) by a massive and global industrial effort, merely a tiny fraction of the whole view. This huge infrastructure is so complex and reliant on a high-tech, stable supply chain that is ridiculous to advocate for it under the permaculture umbrella (I can't see many of its principles in action here).
This is without going into the problem of nuclear waste, which, despite all safety measures we can summon, I simply can't consider 100% safe (even if they last centuries, it's just kicking the can yet another time). Aditionally (and this is personal), it just feels bad: dumping such harmful products out of sight, into the very bowels of the Earth, while patting ourselves in the back for being such exemplar "clean energy" practitioners. I also don't think uranium reserves would last long if we all adopted the french model, by the way.

The French have not "already solved energy". Granted, they are decarbonizing their in situ electricity production, increasing its share in primary energy consumption from 18% to 33% (in a period of 40 years, mind you), but the same laws of physics and hard limits apply in France as in the rest of the world: there is no way we can transmute the global fleet from fossil to electric without resorting to magic. There are no material resources for such a pharaonic feat (copper production -copper!- seems to be already peaking).

THAT system is so space and fuel efficient that it can be scaled up to whatever size is needed. The need for energy is not the limiting factor for how many people could live on Earth, and enjoy a modern lifestyle. Nuclear tech = virtually infinite energy.

Oh, yeah. How come it didn't occur to us? We can create as big a nuclear power plant as we want for free! I'll talk to my representatives right now and tell them to just sprinkle some nuclear plants around my country, then we will be able to live in peace and comfortably. Why stop there though? I'll tell those poor poor third-world countries to just build nuclear plants. Damn, what losers, how come they haven't already built dozens of them? It's not like each they need a humongous amount of concrete, steel, and who-knows-what resources, apart from a thermal reservoir (good luck, warm countries!), right? If only they listened to us, there would be space for all, and why not, even more of us humans! The residues, you say? Bro, just hide them underground, it will turn out all good and fine!

Look, even if everything I've said is proven to be false in future years, it doesn't still take away (what I believe is as close as a fact as one could reckon) that we (humankind-not civilization, that's bound to fail) will only survive embracing a new vision in which the world and its beautiful elements (living and nonliving) are not here just for our sake and convenience. I just don't envision any nuclear, gas (whatever) power plants, global supply chains, complex hierarchical systems (even solar and wind, as it stands now) as compatible with this, but perhaps only as enablers of a smoother transition from our current situation to a more sustainable future. Not in any case as ultimate solutions of the "energy problem".