The Urban Dictionary has an interesting definition for "Unicorn" that fits Q Teams post regarding pompous government officials. I think this meaning fits that Q post narrative better.

"Unicorn #12

The upper class of the equestrian world. Because of their magical powers and sociopathic tendencies, they are typically land owners, government officials, and general rich, pompous douche bags. They often look down on and exploit the other species- most especially the ponies. Because of their arrogant, self centered nature, and frequent impotence on the part of the male, they have a high divorce rate and combined with the likelihood of being hunted down by goblins for their magical horn, consequently low population- much to the relief of the other species.

That unicorn paid the police to evict all the ponies from their land. I hope he's hunted down by goblins.

#1%#snob#yuppie#rich#sociopath"

https://www.urbandictionary.com/define.php?term=Unicorn&page=2