The Taurians don't value personal freedom above all.
The founders of the first colony were looking for freedom from social oppressors and tyrannical governments - they were fleeing the Terran Alliance, which was a strongly autocratic nation (at least in terms of everyone being subordinate to Terra) whose response to the desire for independence was to send in the troops.
Richard Calderon's offer to the planets/systems that joined together to found the Concordat was:
To the newcomers in the region, Richard offered friendship and his unswerving determination to maintain a strictly "hands-off" policy regarding their internal affairs. In return for his technology and protection, Richard asked only that they be willing to contribute to the common defense against any and all aggressors.
So, each of the planets/systems could administer themselves as they saw fit, and could benefit from shared technology, in exchange for contribution to common defense. That's minimal interstellar governance, and minimal interference from the state in the internal affairs of the planets, but those planetary governments could be whatever they wanted - oligarchies, autocracies, democracies, the whole shebang.
Shared defense is a common good. Things like universal healthcare and education are also effectively a common good - they benefit all of society. When the Periphery Uprising began, it began with a group of Taurian worlds declaring themselves independent, and the Protector telling the Star League that it was an internal Taurian affair, not a Star League matter. That's an extension of their internal policy towards the Taurian state being applied to the Concordat as a part of a higher state again. States can have high taxes and a broad level of social services like healthcare and education without being intrusive or restricting personal freedom. Conversely, "free societies" marked by minimal government services, regulation and taxes have a tendency to centralise power in the hands of the few, through the acquisition and of wealth, and control over it's subsequent disbursement. The Taurians theoretically have a society where you pay taxes, and in exchange, the government gives you protection, education, healthcare and the guarantee of a minimum living wage - so that you have the standard of living, education and good health needed to exercise your personal freedom in the pursuit of whatever your interests and nature are. Conversely, without that standard of living, education and good health, personal freedom - particularly in a lower-tech level state, on planets which are in many cases not idyllic garden worlds, could/would very quickly become the freedom to become a subsistence farmer, to starve to death, to die at an early age when you can no longer labour physically to continue eating, and where wealth becomes hereditary and a means of control.
Freedom comes in different flavours.