> An experienced C and assembly developer can take almost any piece of assembly code and easily write C equivalent of it...

If the assembly was originally compiled from C, the new "C equivalent" can have radically different flow than the original had.

Modern compilers can do rather crazy and surprising transformations to your code.

They might omit large chunks or even turn your loop structure "inside out" to enable vectorization optimizations.

They can pattern match your algorithm and replace it with something faster. See: https://lemire.me/blog/2016/05/23/the-surprising-cleverness-...

I can do the same with e.g. Turbo/Free Pascal, yet no one claims it is an high level Assembler.