Yes, it can be very real, and very upsetting to people.
I'm that way with spiders. I not only freak out, but also get nauseated and feel like I'm going to have a heart attack !!! Even pictures make me queasy. It has gotten a "little" better, but still...
Of course, where I board my horse there are many, many brown widows and other assorted spiders. Not to mention the wolf spiders around our pool.
I once had my horse tied, washing her, when I felt a "tickle" on the back of my shoulder. Thinking it was a fly I just kept shrugging my shoulder, trying to get it off. Finally looked over my shoulder at a big, fat widow.
O>>>>M>>>>G
The screech I let out could have woken the dead. I simultaneously threw the horse brush into the air and smacked the spider off. The horse spooked so bad, she broke free and ran for her life...lol. Thankfully I wasn't bitten but I kept thinking I was, because I felt ill and light headed.
So yes, phobias are very real and can be very uncomfortable. Hence why I'm not a fan of parading my snakes around unsuspecting people in public. I just don't think this is a good way to educate people about the hobby.