Not really, given how e.g. Linux and especially e.g. Fedora now shove almost everything into
/usr/bin. However! You can exclude or include things, depending on whether you have a known list of "only complete on these"
% zstyle ':completion:*:*:-command-:*' fake-always chmod chown
% zstyle ':completion:*:*:-command-:*' ignored-patterns 'ch*'
or want to knock out a few specific annoying conflicting completions that you never use anyways
% exec zsh
% zstyle ':completion:*:*:-command-:*' ignored-patterns '(chat|chroot)'
though future you may end up scratching their head as to why some long since ignored command does not appear in the completion list (no this totally hasn't happened to me why do you ask)
% zstyle | grep command