Whirligig is right about the apparent selfishness of this debate, though maybe wrong to be surprised about it. As I pointed out earlier, we all do a cost-benefit analysis, however imperfect, and use that to decide what we will do to avoid collision risks.
To put it simply, who in this discussion has installed any non-mandatory equipment in their aircraft which:
(a) benefits other airspace users more than it benefits them; and
(b) cost more than they reckon to be the benefit to them?
My guess would be exactly none, though I'm prepared to be corrected.