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...
Well, personally I dont also regret having gotten here in Bitcoin, It actually makes me aware what do different kinds of peiple who has different kind of perspective towards this kind of community acted upon a scenario which may be similar in what happened to your friend, and it that case, we should be acareful also in spending here not everything in here transacts money some of here steal and scams.