Not really, though the functionalities are adjacent and I could see how one would make that mistake. I do indeed use container tabs, and they're a killer feature.

Tab groups are merely organizational, allowing you to reference, store, close, and save groups of tabs en masse; by contrast, container tabs don't do ANY organization at all; you can't group them all together, move them all to a new window as one, bookmark them all, close them all, etc.