It seems to just kind of be a necessary thing, imo
Without it being retooled to be massive bonuses (to the point where they would almost always win a grapple anyways), Freedom of Movement is one of the only answers to truly grapple-focused enemies.
Their bonuses scale quickly to the point where Full BAB, High Strength characters can struggle to succeed against them, and the Caster with 1/2 BAB, Low Strength, and possibly even a size penalty, has next to no chance.
That being said, Fly is available a level sooner, and shuts down a lot of grappling (unless they can also fly), albeit for a shorter amount of time.