I am a bitcoin owner.
That said, I agree that the PoW mining reward is excessive.
Right now, a 51% attack on the network costs upwards of $2M/h[1]. That is an obscene amount. I argue this comes from the very high growth not being expected by the creators.
Most of the miner rewards right now come from inflation (in spite of inflation being less than 2% per year). This was intended to allow the network to grow permissionlessly - so, anyone can sacrifice real-world resources for some tokens, and they don't have to buy from someone already owning it.
The reason such a sacrifice is required is that you need a form of scarcity to prevent a Sybil attack[2]. Otherwise, a single person could spin up countless VMs to fake identities, which would be unfair.
Since everyone must have heard of Bitcoin by now, I believe this high reward is no longer warranted, and results in a lot of waste. It should be reduced, to reduce the electricity budget of miners. A larger share of this cost should be borne by people actually using the service - i.e. transaction costs.
I believe that Bitcoin should reduce its block time, in order to trigger the reward halvings more quickly.
[1] - https://www.crypto51.app/
[2] - https://en.wikipedia.org/wiki/Sybil_attack