Learn Finnish: Kasvatus toimii hyvin, sikäli kuin rajoitukset ovat reiluja. - Parenting works well, insofar as the restrictions are fair.

No, it typically uses the standard indicative mood, as seen here with ovat. While it translates to a conditional idea like "insofar as" or "provided that," Finnish treats the condition as a real, evaluated state rather than a hypothetical one, so you do not need to use the conditional mood like olisivat.

Why is kasvatus translated as "parenting" rather than "education"?

While kasvatus can mean education, it specifically refers to upbringing, raising, or cultivating (from the verb kasvaa, to grow). Academic schooling is usually koulutus. In a context discussing rules and boundaries for children (rajoitukset), "parenting" or "upbringing" is the most accurate translation.

Why is the adjective reiluja in the partitive plural instead of the nominative plural reilut?

In Finnish, when a plural subject complement (an adjective describing the subject after the verb "to be") describes an abstract concept or a general quality, it takes the partitive plural. Here, it describes the general quality of the rajoitukset (restrictions) being fair.

Is the comma before sikäli kuin strictly necessary in Finnish?

Yes. A strict punctuation rule in Finnish is that subordinate clauses must always be separated from the main clause by a comma. Because sikäli kuin introduces a subordinate conditional clause, skipping the comma would be a grammatical mistake.