> receiving faster or better care because you can pay more is fundamentally unfair
It's considered fair exactly the for reasons you have mentioned: you pay more for a premium product.
> there's no room in a just society for a "basic service" which does not provide the best possible care.
A regulated market that denies individual differences and enforces the same salary for different talents is incompatible with a "just society". In this case, healthcare workers with above-average talent would emigrate to a country where they can get a fair salary.
If you are worried about fairness, please consider the other side, the healthcare professional who provides the service.
Patients who pay basic fees are not entitled for the "best possible care". The provider of the "best possible care" can raise the price anytime. There is no economic justification for price rigging.
Or you can do it en masse in the browser: https://lifehacker.com/how-to-disable-all-retweets-on-twitte...
I prefer individual control over central control. Maybe they should make the "Turn off Rewteets" feature more visible.