The supply dictates the price. Thought experiment:
Imagine any item with a certain amount of demand. Now cut the supply of that good in half. What happens to the price?
If the supply gets cut in half, then cut in half again, and again, what happens? If we accept that the mining reward is the "supply" then we can see that it should cause continual increases.
As for the already-emitted supply, you can essentially ignore it because of self-interest. Seeing the effect of diminishing supply and unlike miners, not needing immediate funds to buy new mining hardware to stay competitive, for currency hodlers, HODLing is the rational strategy. So holders aren't really part of the supply equation, hence the "store of value" narrative.
So you've got a dwindling supply flow, that causes higher prices, which, because of built in competition, guarantees that the blocks will go to whoever is willing to expend the most energy to get them, which is a ceiling only provided by the current price, which is ever driven higher by the increasing exponential scarcity of the halving block rewards.
Essentially, this scheme ends with the heat death of our planet, and unlike climate change, green energy might not be able to make a dent in time.
The halvening stops in 2140, if I remember right. Humans intuitively don't understand exponential growth well, but if the same path continues, the energy growth (halvening = price doubling)
1 = Today = ARGENTINA's energy usage
2,4,8,16,32,64,128,256,512,1024,2048
In 40 years, 2048 times that. And it just goes up from there. Now, if you're thinking, that's more than the world produces, you're right. But what happens if it is even half, or 1/10th as bad? Still nothing that leaves us a habitable planet, because the heat and carbon from mining will drive climate change past the brink.