I was reminded later that there's a gun available that specifically says it's good at breaking shields like the boss has, which also is used by the guy you fight before the boss to make sure you remember it exists. I went back and tested it out, and it seems better than the machine gun I used but not by a super huge margin, so I get to feel a little bit dumb but also a little bit more skilled, as long as you don't count using the right tools for the job as a skill.

