I know a bunch of languages too, or at least I claim that I know, because I've used it for some time in the past. And I do not remember the most of them, in the sense that I cannot right now start writing in those languages. But I can start to write C or rust without need to take a look into a tutorial or something like, because I use them routinely.

After lisp I've lost the idea of syntax as of an inherent part of language. You know, all that stuff, that lisp's s-expressions and their memory representation are mapped into each other seamlessly lead to a conclusion that any of them is not important, there is an abstract idea of a lisp object while conrete representations of lisp objects are just some practical ways to deal with them in different situations.

So the official language syntax is a one of the practical ways to represent ideas using that language. The most of languages do not bother to have a second representation, but it doesn't matter. Syntax doesn't matter. You can learn it on a whim in a half an hour of leizure reading.