i can only guess:
make the operators buy the RNP AR approach.
if they have 95% of flights with approval they can work the RNP approach with 500' minimums maybe.
when the minimums are 2500' so the RNAV Visual can be used there is no real need to fly that approach. traffic wise that is, would still reduce noise i guess.
so pushing more airlines towards the RNP seems logical.
VOR22L has 440' minimums so that fits well for running interleaved 22R and 13L down to 500' ceiling.