Sure, people will always take God's word and twist it to fit there own agendas. This doesn't mean that part of the old testament is thrown out. Yes Jesus corrected people where they were twisting things for their own selfish purposes. And yes, Jesus made a new covenant and the old one was made obselete. A lot of confusion comes in about that.
Maybe that is what you are meaning here. Yes I would agree with you, if that is what you are saying. The old covenant was flawed the bible says, but it was not flawed because God made a mistake, but because the covenant was able to be broken by an unfaithful party, and so it was broken. So God made a new covenant, one that could not broken by an unfaithful party. This was God's plan all along. He did it this way to show us that everything is about His grace, and nothing we do to earn anything. This all gets complex, but at the same time it is simple once understood.