Interesting question, I know. For me personally the answer is no - I have not ever regretted having gotten into bitcoin, despite having spent hundreds and hundreds of hours researching the topic. It's always been an interesting ride.
But I have a friend who got scammed and he regrets having had anything to do with crypto in the first place. It's pretty sad but there's nothing I can do about it. I even offered giving him half of the amount he lost from my own crypto stash (mind you I am not rich) but he's so scared that he's not interested any longer...
Your friend, I think, suffered because of his carelessness and inexperience. I think that because of one time he should not be disappointed with the cryptocurrency. It is important to understand that now we have really great opportunities, and your friend can miss everything.
