Yep. Executables are section 1 simply because they came first in the binders.
There's nothing necessarily preventing man from allowing string codes as a replacement, but man interprets (fully) non-numeric arguments as pages to go. So `man cat dd` (on Ubuntu) will first open cat(1), and when you exit (with 'q'), will prompt if you want to continue. If you say yes, it'll open dd(1).
That has the side effect than `man exe dd` would be interpreted as opening exe(#) (printing "No manual entry for exe") followed by dd(1).
There's nothing necessarily preventing man from allowing string codes as a replacement, but man interprets (fully) non-numeric arguments as pages to go. So `man cat dd` (on Ubuntu) will first open cat(1), and when you exit (with 'q'), will prompt if you want to continue. If you say yes, it'll open dd(1).
That has the side effect than `man exe dd` would be interpreted as opening exe(#) (printing "No manual entry for exe") followed by dd(1).