You are looking at the circumstances of each individual dictator which is valid. I’m speaking in a macro sense — what the populations exposed to the religious traditions did. It may be unfair in that the line of freedom is a brief moment historically in Greece and Rome and then the Anglo/American line which is very young historically. The Anglo American line arose in predominantly Protestant lands rather than Catholic lands, which may be an accident historically, but it seems connected to me.
First, the Greco-Roman world is a world where tyranny and absolutism were the standard and popular government was intermittent.
Second, the Anglo-American world picture - where the executive is subordinate to a legislature and the people have specific rights and remedies against the executive - was formed in Catholic Europe. Protestantism did not introduce the Magna Carta or habeas corpus or parliamentary government to Britain. These were innovations created by Catholics.
In medieval Italy, Switzerland and the Low Countries, various forms of republican and popular government were introduced. Entirely by Catholics.
Protestantism did introduce the aforementioned dictatorship of Cromwell and the protofascist regime of the kingdom of Prussia, however. It also introduced the doctrine of the divine right of kings.
If anything is to blame for the decline of free institutions in continental Europe in the modern era it is the Thirty Years' War: an initially religious war waged by Protestants against Catholics that turned the continent into one large armed camp.
An entire generation raised in a militaristic, embattled atmosphere created the conditions for Europe's subsequent lack of liberal institutions.
The British navy and the English Channel, not British religion, kept Britain free by isolating it from the continental devastation.