I don’t know any millionaires from crypto. I know people who are loud when market is up and very silent when it’s down. May be they were millionaires on paper at some point. Highly doubt they sold everything at the right time and became actual millionnaire. But sure, it did happen for many.
I mined a "bunch" back in 2011 or so, lost the hard drive with the keys on it in the years since, didn't really think about backing it up, because of course it's not worth anything, etc, etc.
If I had that drive today, I'd be a millionaire. But also, if I had that drive in 2013, there's absolutely no chance I would have held it. I would have sold it for a few hundred bucks and been elated.
A friend got a great job, if I hadn't failed job interview X I would have a great job. Later you find your friend hated that job; your experience of the job you "missed" is unknown, etc. It's also part of survivor bias.
What would it have taken in advance for you to not cash in that early bitcoin that you didn't get (or lost) and didn't expect would become anything? Is that something you can prepare yourself for now? Is it worth preparing?
Deciding you have a financial portfolio, and framing that one part of it is risky, and another part is experimental, and then placing early bitcoin ownership as part of the experimental portion of your financial portfolio, and then later (as it becomes a larger percentage of the total) as part of the risky portion, and then looking for more situations that seem like it could fit this approach could possibly be one takeaway ... but it seems like a stretch.
You also have to avoid patterns that cause long-term failure but are misleading in the short term, such as buying and selling to realize gains, but then repeating ("it worked once") buying and selling until you have an overall loss. Like gamblers do. Sometimes they win, somethings they lose, but they lose overall by not ever stopping.
Also, how do you know someone who seems to have succeeded isn't simply in the "looks like success" portion of long-term failure? How would you avoid it?
Just because someone was actively monitoring crypto & then missed out as the price went from $1 to $10,000 still doesn't mean they have misjudged. Even if crypto is the future - and I've become convinced that it is for privacy reasons - there was still scant evidence of that during Bitcoin's rise. There have been no great arguments circulating to explain why someone should buy in and a lot of the people who made money look like they just got lucky.
It's like if you see a friend betting a bunch of money on a long-odds horse and then winning. You exercised good judgement, but he won anyway. Do you feel penalized for applying your better judgement in that situation?
The only thing that really matters is: was it the right decision given the information you had at the time?
But “better judgement” said that it’s a currency it shouldn’t appreciate so why bother unless you want to actually use it?
So if there’s regret it’s because many of us feel almost penalized for applying better judgement. It’s like you’re rewarded for stupidity. Not a single person I know and actually respect invested in crypto, and half brained idiots I know have become millionaires. So yeah this is not like horse betting.