Federal judges make lots of wrong decisions that get overturned on appeal.  The stronger case is that the Executive has the authority to terminate any employee under the Executive branch - this means there could have been two responses by Nixon either of which could have succeeded.  First, he could argue that the President is the arbiter of what constitutes "impropriety" in the Executive branch and second, he could simply appeal on the basis of the law being an unconstitutional restriction on the powers of the President.

This would have been exactly the type of disruption Bork  successfully avoided.  BTW, straw man arguments like "is actually supporting the idea that the president is king and above the law." are just confirmation that you are not keeping up with the debate.