The article signally fails to remark that for the majority of any society human rights and civil liberties will be something that stops the state acting in their interests.
For example, it is in most people’s security interests for the state to be able to summarily execute anyone it suspects of involvement in terrorism. Should it be able to?
I doubt many people think it should. As we see whenever any court defends human rights, the government does not object specifically to the ECtHR—it objects to whoever is defending human rights. And if we withdrew from the Council of Europe, shortly after we should expect the Human Rights Act to be repealed (to be replaced with something far more amenable to the exigencies of the government of the day).
And the individual would be left with little protection from any oppressive whims of the government.