I would put this in the "speculation" bucket.
First: as surprising as it may seem, not all miners sell their coins (it's cheaper to mine coin than to buy them, therefore someone wanting to invest 10M in BTC is better off buying mining equipment and paying for the power to run it).
Second: it's very likely that, the exact supply of Bitcoin there ever will be being a known quantity, the "cost" of as-of-yet-unmined coins is priced in.
14 billion what to maintain the current price? How does that work?
And I guess XY = $14 billion but I haven't bothered to look the numbers up.
Here's the previous day's block reward and current price. https://bitinfocharts.com/bitcoin/
The other thing about mining is the their costs are in hard currency, so there's not much opportunity to "hodl".
Those mined coins need to be sold once the electricity bill is due, so to maintain a stable price bitcoin needs an ongoing net dollar investment proportionate to the current price (taking halvings into account).
It takes about $14 billion per year to maintain the current price given that new bitcoins are "mined", so that's the theoretical supply inflation right now not subtracting deflation from lost coins.
The gambling industry worldwide revenue is $219 billion.
That's just one theory of its value if its purely used for speculation. That said I still believe it could totally collapse at any time or perhaps hit an all time high and slowly decline from there, with several smaller rallies on its way down.