Hello,
I must say yes and no, I believe that ATC's will remain proffesional irrespective of their employer. I have seen (and worked) this in the past.
Privatisation has a good side as well, it can generate a phenominal amount of technological advance in the procurement of new equipment. It can cause the streamlining of management and weed out the deadwood.
The down side of privatisation will tend toward the beancounters chasing the "buck" and trying to save where they can.
The point is, that the Civil aviation authority will (and should) always be RESPONSIBLE for air safety and in that capacity they should act as regulators to ensure that there are limits which the "private bosses" may not overstep.
Allow the privates to take over the running of the system, keep the govt involved in a standards and regulatory role.
My thoughts.