To preserve our constitutional scheme of liberties it is imperative that federalism and the separation of powers be taken seriously. That means the federal government shouldn't act outside its express and implied powers. And it means that each branch of government must operate within its own sphere. The legislative makes laws; the executive enforces them; and the judiciary interprets them.
Each time the federal government usurps power intended for the states our freedoms erode. Each time one branch assumes a function of another our freedoms erode.
One of the primary functions of the federal judiciary has been to prevent the other two branches from acting beyond their constitutional authority. It was also intended to prevent federal encroachments on states' rights, in other words, to honor the federalism doctrine. Only in recent years has the Court begun to resume that important duty.
The judiciary, however, was designed to be a passive branch, deciding legal disputes (cases and controversies) among people and interpreting the laws, including the Constitution, not making the laws or creating new constitutional rights, such as privacy. Judicial activism occurs when the judiciary makes rather than interprets laws.
So it was wholly proper (and not judicial activism) for the Supreme Court to bar federal suits by state employees against their employers under the Americans with Disabilities Act when the 11th Amendment to the constitution forbids such suits. It would have been improper judicial activism for the Court to permit such suits just because a majority of the judges happened to believe it was a desirable policy.
To the Times conservative judicial activism is when the courts refuse to implement liberal policy, even when doing so would be outside their constitutional authority. It's kind of like the Soviet Communists defining imperialism as the actions of any foreign power standing in the way of Soviet territorial expansion.
The confirmation of Jeffrey Sutton to the appellate bench will not be a triumph for ideological conservatism or judicial activism, but for judicial restraint, the separation of powers, federalism and freedom itself.