There is no point in regretting such things. You could not have known what would happen to the price of Bitcoin. You probably would’ve ended up selling it for a tiny profit and then you’d still be regretting your actions, or even you could’ve panicked at some point when it dipped a little bit and sold at a loss.

I wouldn't beat yourself up over it. As other commenters have pointed out, nobody knows or could have known where Bitcoin was going to go, unless they were in control of substantial liquid leverage and knew that they could constrain supply indefinitely.

And even then, holding a corner on supply of an untested asset is still no guarantee it will perform. Sergey Brin and Larry Page tried to sell Google to excite.com for a paltry $5MM ... and Excite turned them down. Even they, who of all people should have had the utmost confidence in the future (and control over supply)of their own brainchild asset, didn't fully understand the significance of what they were sitting on.

I was talking with my wife (then gf) about putting $1000 into BTC back when it hit $1. I don't let it eat me up though, I'm not a gambler, and it's quite likely that I would have sold at some point.

Though.. if I had my wits, hopefully I'd be selling off chunks. Ie, at $18k/coin I wouldn't sell the whole thing.. though, at only $100/coin it would have been tempting.

Ah, life.

Ask your uncle his thoughts on investing in baseball cards and comic books, too.