If they ship 100k in France alone on Day 1, then how many would they ship in Germany? Spain? The UK? The US? Japan? If the other Western regions are relatively similar to France in that scenario, they could reach 1 million shipped in that opening weekend, let alone the end of December.
France is Nintendo's biggest market in Europe. I can imagine them shipping 300k+ to the US day one. Japan though has never been a big market for Metroid outside of the original selling 1mil and Super Metroid selling 500k. All other 2D Metroids sold below 200k. So 100k day one is not likely because it could pose the risk of overshipping.