You may as well just say "Always attribute everything to malice whenever possible." Hanlon's razor is only necessary when both stupidity and malice are plausibl

You may as well just say "Always attribute everything to malice whenever possible." Hanlon's razor is only necessary when both stupidity and malice are plausible explanations, so your "exception" applies 100% of the time. By this philosophy, we must always attribute deeds to malice whether or not they can be adequately explained by stupidity, because even when mere stupidity is sufficient, we must still read in malice.