FWIW I use zsh with auto-auto-completion / auto-completion-as-you-type, so just hitting `p` on an empty command line will remember the most recent command starting with `p` (which was likely `pnpm`), and you can refine with further keystrokes and accept longer prefixes (like I always do that with `git add` to choose between typical ways to complete that statement). IMO people who don't use auto-completion are either people who have a magical ability to hammer text into their keyboards with the speed of light, or people who don't know about anything hence don't know about auto-completion, or terminally obsessive types who believe that only hand-crafting each line is worth while.
I don't know which type of person you are but since typing `pnpm` instead of `npm` bothers you to the degree you refuse to use `pnpm`, I assume you must be of the second type. Did you know you can alias commands? Did you know that no matter your shell it's straightforward to write shell scripts that do nothing but replace obnoxious command invocations with shorter ones? If you're a type 3 person then of course god forbid, no true hacker worth their salt will want to spoil the purity of their artisanal command line incantations with unnatural ersatz-commands, got it.