> You might not, I do.
Then you don't want a currency. For something to be money it needs to (among other things) be a medium of exchange, and nobody really wants to trade away a thing today if they know it will be more valuable tomorrow.
Suppose you have some control over currency. You run a country. I'm that case, so you still want the currency to gain value compared to the alternatives?
Your choice is basically: holding currency is more profitable than building a house or running a business (or lending to those who do), or else less profitable. If you run a country, do you want houses and jobs and all that kind of thing, or do you want people to do better if they choose to hoard currency?
If I need a house today I'll buy it. I might not invest in real estate or stocks as much if my currency will be worth more tomorrow but I'll still buy stuff I need or want badly enough.
The bond seller is intending to put it to productive use to generate the yield.
This differs from deflation where people will (more the before) actually sit on money and not buy bonds. Then people who need liquidity cannot get it as the money supply drys up.
SPY has outperformed BTC over the last 5 years, and with far less volatility.