A good interviewer could ask some questions to find out if the answer is just memorized or if they understand the concept. And it would test your willingness to educate yourself on a domain, which is something I would value in my team.

And I say this as someone who doesn't particularly like the modern tech interview style, I think actually trying to build something is better. However, it does have some merit in measuring a candidate's ability even if it's not necessarily that great.