For the same reason people still go to astrologers or think that during the playoffs the can't shave or their favourite team will lose: cognitive biases and wishful thinking.
* https://en.wikipedia.org/wiki/List_of_cognitive_biases
The fact that the bubbles happen so often and and so drastically is another reason that I avoid it: volatility is generally a proxy measurement of risk, and what reward am I gaining by taking on this risk?
Everyone is bullish on it at >US$ 40K, but people seem to have forgotten that it dropped by half in two days in March 2020:
* https://www.cnbc.com/2020/03/13/bitcoin-loses-half-of-its-va...
If someone wants to have it in their 'portfolio' at some small percentage as part of their "play money" that's one thing, but to make it a significant portion seems foolish to me.
I do feel a bit of FOMO, and may eventually create a trading account with like 5% of my portfolio for playing around in WSB and Crypto and such, but right now I'm fully invested in index and bond funds (80/20), so don't really have spare cash available for any of these temptations.
I agree but that doesn't explain why Bitcoin had multiple bubbles and survived all of them. Bitcoin is highly deflationary. Bitcoins are lost all the time. The supply is only growing very slowly. It's also an "immature" asset compared to gold so a large influx of a new class of investors can drive the price up.