This doesn’t stop anything though again. Unless you tax them out of business, they will still be a monopoly and will fix prices for their profit. Less profit is still profit.
If you tax them too high they will either seek recourse via illegally bribing politicians (or “lobbying”) to have those taxes removed, or monopolise with legally distinct businesses where wealth is concentrated in the few regardless.
That’s where you have to tax monopolies.
Monopolies will resist but it takes only some expropriations to motivate shareholders that they push for law-abiding behavior.
This doesn’t stop anything though again. Unless you tax them out of business, they will still be a monopoly and will fix prices for their profit. Less profit is still profit.
If you tax them too high they will either seek recourse via illegally bribing politicians (or “lobbying”) to have those taxes removed, or monopolise with legally distinct businesses where wealth is concentrated in the few regardless.