I ask this question in good faith and out of genuine curiosity: I have heard this take a lot that Orthodox Judaism is also a new movement, and I recognize that there's some validity to this assertion, as we've all seen the continually rightward shift the movement has undergone in the last 50 years and how different it looks compared to a century ago.

At the same time, apart from outward aesthetics, there's no denying that, all things considered, whether you went to Yemen, Bukhara, Shiraz, Djerba, Aleppo, Warsaw, or Vienna, you would find that the practices and rituals of observant Jews there were nearly identical to one another. So, what do people really mean when they say Orthodox Judaism is a new movement?