This seems like a card that only does the thing it appears to be designed around in one deck -- namely, the Nathaniel Cho starter deck, where almost all of your fight actions are going to be from playing an event (or just a basic melee to finish off odd-health enemies).
For other investigators, the Boxing Gloves make an awful main weapon. But that doesn't mean they're useless, since if you can include Boxing Gloves in your deck you can include Bandolier and another Guardian weapon (even a two-hander if you use upgraded Bandolier). That +1 while fighting works while you're using another weapon (as does the search effect), and while having to find your Bandolier (and forego the use of an investigation tool) first makes them harder to play than Ace of Swords, there are probably decks that would love to run both.