This might have been (see my other comment) a technical limitation at the time, but it also might have simply been the nature of Unix.

Remember that Unix was created in response to a disastrous dis-engagement that Bell Labs had just had from the Multics project, where source-code and file-name verbosity was the rule of the day, and I imagine one of the disaffections involved was the absolute baroqueness of the Multics naming conventions.

(E.g., random source code example of the Multics sources: http://web.mit.edu/multics-history/source/Multics/ldd/system... .)

So when you're using library and program names all day that are terse by design (ln, ls, awk, ed, etc.), "create" looks positively sesquipedalian.