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I don't think people are dumping on the "idea" of a soulmate as much as they are dumping on the "notion" that a finding a soulmate should be part of some mythical quest and requirement for people. Especially before they meet someone. I think it's more of an anti-process thing rather than anti-soulmate thing.
Anyway, I'm glad for you, but, you're engaging in what's called hindsight bias. People meet and click instantly all the time. Most of the time it turns into nothing. I suspect your story might have been a tad different if he/she turned out to be crazy or something after you went out on your date. Despite your initial "click", you didn't know your sweetie was really soulmate until the "happily ever after" part. But, it's nice story.