I'd just deal with this like any other irrational fear my dogs may have.
With TRAINING and treats. Real treats of chicken/cheese/hotdogs/meat.... and a hungry dog.
If you clicker train this will go really fast.
When you see a person (or anything that bothers your dog) WAY far away and your dog looks at them, you click/treat (the dog has to be quiet and calm). You have to either be silent or happy sounding.
Go closer, when your dog looks at the 'whatever' you again click/treat as long as your dog is calm and quiet. Continue going closer as long as your dog is calm.
Put yourself between your dog and the whatever. Very bad to put them into the position of being ahead of you and forced to greet the whatever first.
If you have to sit across the street from the whatever, and when ever you dog sees his trigger thing and is just looking and quiet you click/treat... that's fine too.
You can ONLY do this when your dog is calm, if you go too fast in the training and your dog reacted then YOU were a bad trainer and lost the teaching moment. They can't learn when they are FREAKED OUT!
This is one of the many many reasons I continue with socialization and dog CLASSES for years if I have to. It exposes them to every thing all the time and gives me the skills to help my dog get thru new things. Elevators, giraffes, hot air balloons, goats, rabbits, kids on skateboards, WHATEVER.
My dogs learn that if I am happy and calm then it must be ok, and they take the cue from ME. Watch ME. See my reaction (or lack of). If I say it's ok, then it is (and probably it is with a cherry on top

(or chicken or cheese or hotdogs...)) My dogs don't think I put them in charge of a horrifically scary situation that they have no skills to deal with appropriately, so instead over react AND IGNORE ME.
I got it! Really! Get behind me an I'll deal with it if you are worried. So next time you'll see I was right and it was ok!