Not my experience at all: ALL levels, besides maybe junior which kind of doesn't really exist in Big Tech, require system design, so I can't really relate to this. Algorithms are usually about specifics of what the company itself does, so expect graph traversals, networking, file system stuff etc, disguised as a puzzle depending on the company. Nobody will ask you about "generic algorithm questions" and actually the "topics" are quite narrow.

What I'd like to know and see written down is how you truly prepare for system design when you DON'T HAVE or CAN'T GET experience with large scale systems at your DAYJOB. The chasm here is that when competition is other 20 engineers who just memorize things, even if their actual relevant skills are objectively worse than yours in practice, you'll never, ever get the job. It's a very tough game and I admit there is real skill in knowing how to game the system :) it is what it is.

PS: I know exceptions are everywhere but I'm sure that the quality of the ones who get in vs rejected will be basically the same. It's just a process optimized to minimize false positives, so, only the median will get in, really good ones will be rejected and only maybe a very small fraction of the ones who make it through will be "The real deal".