Fixed supply is a form of scarcity, the absolute form…re your second point, it‘s a trade-off that ultimately negatively impacts Bitcoin‘s immutability. Bitcoin optimally solves for one human problem only, money. One has to be careful not to superimpose trying to solve unrelated issues on it, that dilutes the purity. It’s like saying we are limiting free speech to solve child pornography….Bitcoin has enough privacy for two peers to transparently transact with each other, they have to trust each other. The invasion of privacy by a third party is unacceptable and has to be solved directly.
Discussion
Ok true, absolute scarcity is a fixed supply. But a private transaction is really hard because of the on-chain transparency. If we do a transaction with a change output included I always have to take care of the future usage of this change output. If we do a cash transaction where I get some money back you can't see what I do with the change.
It's a fallacy that absolute scarcity alone automatically = more valuable
You can fix the supply, but you can't control demand. Ultimately value is subjective like any good bitcoin maxi austrian should know. And demand can change at any time.
On-chain Bitcoin has some anonymity if done correctly, but can never have privacy. Big difference between the two. It's a transparent public ledger.
https://github.com/libbitcoin/libbitcoin-system/wiki/Scarcity-Fallacy