Yea this is how I try to think about.

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.

There is so much adaptation overlooked in any thing (item, experience, relationship, etc). becoming a thing of value, and so missing frames of references of this type occur frequently.

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?

Same for me. I actually tried to find my wallet in around when it went over a few hundred dollars.

Exactly, the fact that an assent went from $20 to $20,000 once doesn't tell us much. This is why in financial economics the variable of interest is returns, not price. Statistical analysis of returns will tell us what return to expect if we hold the asset over a random time period of a certain length, which is what happens in practice.