~snip~
The main reason is legal. In many countries, including where I live, BTC payments are banned and seen as a threat to the national economy because it can mess with the value of their own currency. Personally, I've never been able to spend my sats on anything because no one dares accept BTC payments.
Another reason is related to the investment mindset. BTC holders always have this feeling that BTC price will keep going up, so spending BTC today might feel like a mistake. I haven't sold any of my BTC to buy a new laptop for the same reason. I think BTC will hit $150K-170K in the next few months, and I could buy multiple laptops then ^^
However, if you look at payment with BTC, it is not illegal anywhere in the European Union (as far as I know), nor in the US or Japan, and yet few people decide to make such a move precisely because of what you mentioned. It is obviously difficult to accept that today you spend BTC, and in a few months the price will be 50% higher - but from the famous most expensive pizzas in history until today, people have paid for something with BTC, and I also remember that I bought a lot of things while the price was under $20k, but I don't regret it too much because I bought the things I needed.
I also hope that a big bull run will happen, a lot of people expect it and it would not be pleasant if they were disappointed.

@kai, I guess you know that you don't have to buy 1 BTC, you can theoretically buy any amount depending on where and from whom you buy. If for some reason you can't buy right now, I'll send you a small amount just enough so you can say you own BTC

Of course you need a wallet, I recommend Electrum or BlueWallet - both have desktop and mobile versions.
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