I don't see the value in memorizing programming -syntax-. It's irrelevant to me to remember how to open a file in ruby or do a specific command- that's what search engines and then my personal wiki is for.
If I worked -only- in ruby, then I'd likely remember those specifics much more, but since I hop around with rust, python, c#, clojure ... depending on our clients, there's no way I'm going to remember stuff like that for every language. Especially since languages tend to get updates and changes!
I would use anki to retain knowledge of stuff like more complicated data structures. Right now, I just search for what I need, then toss it into my personal wiki folders. I can then use notational-fzf-vim to rapidly fuzzy search my markdown files. [0] I keep these synced across computers with a selfhosted nextcloud instance.