same here - almost 20 years of dev, last time I needed to implement basic cs algorithms were in college and grad school classes (and some idiotic corporate interviews where preferred way of coding is apparently using a white board).
basic knowledge of fizbuzz, dfs, bfs, quicksort, and similar things of course is needed - however asking developers actually implement them in front of you is pointless, at least as far as job performance goes.
FizzBuzz is not some arcane algorithm. You don't need to study it.
It's literally writing a loop, testing equality, and printing some output. I don't know how you could program professionally and not be able to solve FizzBuzz.
This is the same for a lot of the basic algorithms we learnt and forgot.
This, to me is the big caveat. Just as there are a lot of people who are horrible at solving stuff they should easily be able to, I've conversely seen so many horrible interviewers that under-specify the problems they ask about because they assume people should understand algorithms that would make it easier to understand, or just assume people will infer things most people wouldn't.
"Take these two variables, derpyOne and derpyTwo, and swap their values"
When I studied CS, data structures and algorithms was the second CS course we were expected to take, right after "introduction to programming". It would usually be taken in the second semester.
That's the last time we were tested on a long range of algorithms, except indirectly if we happened to need a given algorithm to complete our work later. In the 22 years since, I've probably needed e.g. a depth first search once, and many of the algorithms I learned I've never touched on since.
So for many, it boils down to whether or not you cared about and liked that course. I happened to love it - I read the set texts the first weekend of the course, and spent a lot of time reading up on algorithms in the years before and after. But for a lot of my class mates it was a course they had to endure to get to more interesting stuff. Many of them would go on to do very well in other subjects.
If they can't figure out a problem like FizzBuzz given a complete description, then that's a deeper problem. But a lot of algorithm questions can sound like they are on that level because we expect people to know a catalogue of algorithms that most developers don't actually need through most of their careers.