[throwaway287391]

> But obviously in hindsight, it was the most expensive mistake I've made in my life.

Maybe a tiresome pedantic response, but this is only a "mistake" to the same extent that it was a mistake for [everyone in the world who had the required funds] not to buy 100 BTC in 2015. If you can overcome the cognitive biases (endowment effect, loss aversion, etc.), the fact that you previously owned the 100 BTC has no real bearing on the situation, beyond transaction fees and a couple hours max saved by holding (doing nothing) vs. buying.

[pjc50]

It was also a mistake for me to not buy a lottery ticket with the numbers 4 11 17 25 41 51.

There's a slow drip feed of stories of people who did buy BTC and have lost it, either to human error, lack of backups, crime, or failure of institutions. Remember MtGox collapse in 2014? The whole fad was obviously over by then, wasn't it?

We're going to have another 2008-style bubble collapse eventually. But it's not clear what the radius of effect will be.