The releases may seem more major than they did in the past because PostgreSQL dropped one part of its version number with version 10. 11 is to 12 roughly as 9.

The releases may seem more major than they did in the past because PostgreSQL dropped one part of its version number with version 10. 11 is to 12 roughly as 9.5 is to 9.6, not as 9.0 is to 10.0