OP - I understand. You didn't think it was working, gave it time for flight to get airborne and even checked vents in the main cabin. You did your due diligence.

The crew didn't know your status, due diligence or experience so assumed you were just a novice travelers with temperature issues/heat flashes.

I've had similar experience with Internet on a plane - advising crew it wasn't working as soon as hit 10,000 ft, they responded (I was the only person) and I should restart my device (I tried it via two different devices), and maybe 1.5 hrs later they announce they are restarting their system (which NEVER fixes the problem).

I think if we acknowledge 50% of travelers take only 1 r/t flight per year - the crew can't react to every cry of wolf. I hate to make this recommendation but maybe worthwhile to indicate you are an Elite status so they recognize you aren't full of BS.

On another note - as the crew isn't tied to the aircraft and simply want to move on - they probably don't wish to fill out the necessary paperwork. Imagine, rental car agency during peak holiday weekend has two cars returned which drivers reports a defect with steering or bluetooth, the return agent can slow down to fill out paperwork or can simply recycle the car and let someone else deal with it when he/she is off shift.

Your issue isn't with Delta but society and apathy.