In what sense is that an answer to "why were they doing that?" The entirety of the answer does nothing but give a name to the policy. "Why" would usually be understood as a question about the reasons behind the policy.
"The government was subsidizing the abandonment of paper medical records because they had a program in place to do that" is something you knew before you asked the question.
Today the incentive no longer exists. Instead theres a penalty in the form of reduced Medicare/medicaid reimbursement for practices that don’t comply.