>

Day/month/year makes the most sense in my mind.
31DEC2022. Leaves no confusion lol >

Is that the model number of some kind of appliance? >

It's the way they write the date in the US Military. >

Don’t know about the military but in the aerospace industry, this is how we put the dates in front of our signatures, when signing drawings and documents >

r/iso8601 >

I will always be a proponent of month/day/year because if someone asks my birthday, that’s how I would say it. 
I wouldn’t say “18th of April, 1983.”
I wouldn’t say “1985, December 3rd.”
I’d say “September 6th, 1989.”
(None of those are actually my birthday) >

Year should go last because it changes the least often.