If we want to be philosophical then answer is very simple. The money comes from people who want to buy bitcoins.
Then we can ask why people want to buy bitcoins and the answer get a bit more complex but usefully branches into two areas. People want to either speculate (gamble) that the coins will increase in value because they think others also think that the value will increase and thus it will, or they want to buy the bitcoins because it enables them to buy objects for which bitcoins serves as value tokens.
Which in turn leads us to ask about the nature of value tokens. Why do we use them, the history, intrinsic values, and so on.
If we want to be non-philosophical then most the value of bitcoin has come from unsophisticated retail investors that haven't spent half as much time thinking about the 'store of value' as you have in this post and just want to make amazing profits like they've seen others make in a short time period.
As far as I know the value of Bitcoin doesn't match the funds invested. So while the money comes from people wanting to buy Bitcoin, the value comes from "the market". But of course then you also have to consider where these Bitcoin comes from. The previous is only strictly true if the person making the donation is a miner or investor. It could also come from selling drugs, hacking or exit scamming.
Then we can ask why people want to buy bitcoins and the answer get a bit more complex but usefully branches into two areas. People want to either speculate (gamble) that the coins will increase in value because they think others also think that the value will increase and thus it will, or they want to buy the bitcoins because it enables them to buy objects for which bitcoins serves as value tokens.
Which in turn leads us to ask about the nature of value tokens. Why do we use them, the history, intrinsic values, and so on.