Well, we know the cause of discouraging VFR to communicate, particularly on FIA & E freqs.
And leaving it up to VFR in overlying E over D to interpret IFR communications and decide if they are going to conflict or not is leaving the decision to (in many instances) the lowest common denominator.
That's assuming the VFR is even radio equipped. As I've said before on this forum, transponders are not mandatory for VFR ops in E for those sports aviation types not capable of powering them.