It may be a good idea to have the tag blacklisted.
I've reached out to Community Managers at the Tavern on the Meta as this can only be done by Stack Exchange employees.
SE developers can blacklist tags so that they cannot be used—attempting to submit a question with a blacklisted tag will fail.
Note that we need to show widespread consensus in favor of blacklisting for this to happen. I can point to "https://meta.superuser.com/questions/8402/manufacturer-company-tags-are-back-again" as evidence of strong community consensus (the vote spread on that question is +45/-1 as of this writing).
