No, it says exactly that.

It is very different than saying “If a law restricting a right is effective, it is Constitutional”, which is not the same as “to restrict a right, it must be effective” (one states a sufficient condition, the other a necessary one.) Nevertheless,being effective is a relevant differentiator between one proposed restriction and another that explains why they might be seen differently Constitutionally, as while a law which is effective at serving some government interest may be unconstitutional, one which is not is almost by definition is not narrowly tailored to serve a compelling government interest.