It was a little different with Bitcoin. There was a time where it was a very passive thing.
You leave the computer on and you mined bitcoins (whole blocks, not just a fraction of a fraction of a reward from a mining group). I left the bitcoin software on for a single week back then. I could have left it on for a few months and mined like 1000+ bitcoins, but I only left it on for a week. I was excited about it too, and thought this could be the future of money, but even back then it didn't occur to me that the price of them would ever shoot up like that. So after a week I got bored and was like "I'll check it out again in a year or so once more people are into it."
You had to actively buy Beanie Babies (or request them as gifts), and sometimes wait in ridiculous lines for hours, etc. A closer analogy would be if someone sent you brand new Beanie Babies for free every week, as long as you said you wanted them.
Granted, you could have taken more active measures to acquire Bitcoin even back then (like that 10,000 bitcoin pizza, for example), but it doesn't require the amount of headspace that something like Beanie Babies would (hunting down the uniques, knowing how much each one is worth, etc). I never got into selling Magic:The Gathering cards even though I played the game for the same reason.
I'm not actually beating myself up about it, I'm just realizing the trajectory of my life would have gone a lot differently if only I let that software keep running several years ago.