But I think it glosses over the most important detail; long-term memory comprises many distinct sub-systems. "Remembering" is typically (IME) associated with explicit/conscious long-term memory processes, but I think the most important thing for learning complex domains like Quantum Mechanics is implicit memory, specifically procedural memory.
https://en.wikipedia.org/wiki/Long-term_memory#Implicit_memo...
In order to understand higher-level concepts like the Schrodinger Equation, one must first thoroughly understand lower-level concepts, starting with mathematical theories like calculus, and physics models of energy. It's not possible to simply fill out an Anki card for these lower-level concepts and memorize the wikipedia page; one must practice performing those mathematical operations until they are unconscious like riding a bike.
This is recursive; one can't understand higher-still domains like Quantum Chromodynamics or Quantum Chemistry until one has worked with the Schrodinger Equation (and other QM formulations) enough that it's deeply lodged in your procedural memory.
This is why it takes ten years to train a physicist (and even then one could argue that physicist is at the beginning of their journey); one must spend undergraduate years working out a bunch of problems by hand, gradually layering new concepts on top of old ones. It's not like pushing a software engineer though a dev boot camp, where a dev can produce something that is simple but useful after a few months. There is no way of usefully abstracting away the lower levels of complexity in Physics.
The other side of that observation is useful too; software bootcamps are possible because we successfully abstracted away a lot of complexity. Good abstractions (even when leaky) can be immensely valuable. Imagine having to do a PhD to have enough expertise to build a web application? I think this achievement is perhaps under-rated, particularly in this community that takes joy in peeling back the layers.
I suppose the other observation I'd make is, don't overuse Anki; it's good for memorizing facts, but not necessarily helpful for procedural memory. You still need to practice doing the thing in order to master complex domains. (I'm open to the argument that having facts memorized might make the procedural acquisition faster, but I'm not certain that it's more effective than just spending the memorization time on focused procedural learning practice instead.)