Why did Paul write Galatians?

https://biblepodcast.substack.com/p/why-did-paul-write-galatians/

To reveal that Christians do not live by a system of rules, but rather by being guided by the Holy Spirit (Galatians 3:3 and 5:16). The law was a guardian until the Messiah (Galatians 3:24-25) and therefore we no longer need the guardian. We are not bound by the Mosaic Law but led by the Spirit. This is encapsulated in the "law of Christ" (Galatians 6:2) which revolves around loving both God and our fellow human beings. This is the essence of the Law of Moses.