You'd be surprised then. A lot of people just apply to jobs and go interview. I never considered interviews something to prepare for until recently, mostly as a result of being on this sub. I remember in my first year at Google, one of the newgrads was talking about Leetcode, and he had to explain what it was to most of the team (including me). I'd note that almost everyone probably knows what it is today.

and it's doesnt have to just be memorization, it's also practice and having similar solutions fresh in your mind.

I definitely think practice helps. It's something of a skill, and you can develop it. My point was mainly that you're not going to get very far with memorization. They're testing your ability to solve logic problems with a programming language. That's not something you can learn through memorization.