How does Orwell compare the farm under Napoleon's leadership to its exploited state under Farmer Jones' rule?

I would say that one of the major comparisons that Orwell
makes between the styles of leadership under Napoleon and Farmer Jones lies in how the
former uses the latter.  Orwell constructs a setting where Farmer Jones is used as the
constant "boogey man" by the Pigs.  Squealer employs the vision or notion of Farmer
Jones as the representation of all that is evil and wrong in the world.  In doing so, he
guarantees that the animals cannot question the world around them.  Farmer Jones is
associated with oppression, unfairness, and exploitation.  In this, Napoleon and the Pig
leadership ensures that he will never be forgotten.  While they are doing this, they are
mimicking the same repressive tendencies of Farmer Jones.  The animals' lives shows no
real sign of improvement as the leadership of the Pigs takes hold.  Each time an animal
raises the slightest hint of questioning, they are accused of wanting to bring back
Farmer Jones and the immediate demonizing of Farmer Jones begins.  In this, Orwell is
making the point that regimes and political orders benefit from blaming their
predecessors while they might be doing the exact same thing in order to consolidate
their own base of power.