VFR is cheaper.
In your April Remarks section, you ask, "Is there a shift away from flying in the system?"
My personal preference is to fly VFR when I can and to use the IFR system only when I must. VFR is much more efficient in time and cost. IFR involves contention for precious airspace with the attendant delays and longer routes. I have found that even controllers like it better when you can maintain VFR and elect to do so, before having to go IFR. It is less work for them and gives them options in getting you across some busy corridors they otherwise would not have.
Because of these factors, I often mix VFR and IFR in the same flight, staying VFR as much as possible instead of going IFR the whole way.
So perhaps there is a good reason to an increased use of VFR.