Bitcoin could have achieved A) through D) by simply doing away with the capped supply and the accompanying subsidy halving needed to achieve it.
Just a pure linear emission [1]. That would avoid the extreme concentration of wealth on early adopters, and make it much less attractive for speculation.
To really deter speculation, one would need to actually increase subsidy over time, but that would make the emission both more arbitrary and resemble fiat.
To really deter speculation, one would need to actually increase subsidy over time, but that would make the emission both more arbitrary and resemble fiat.
[1] https://tromp.github.io/blog/2020/12/20/soft-supply