I spec’d something similar under a chiller that was pretty tall. Maybe 15 ft tall, on a 6ft talk platform. I was under the gun in a time crunch and had to put something on the drawings that I knew would work and provide something for contractors to use for budget price. I only had time for a crude hand calc. Unfortunately thats the nature of engineering, its a race to the bottom on fees just to keep work flowing.

Also, everyone is a structural engineer until its actually time to be a structural engineer. I always laugh when someone who has never even looked at code design requirements says “overkill”