This reminds me of a recent conversation over wearing hi-viz airside at a quiet airfield! A bloke intercepts said pilot at the perimeter. "You're supposed to wear hi-viz airside!"
Pilot: "Who said I wasn't?"
Jobsworth: "The tower! They saw you!"
Pilot: "Well if they have seen me, why do I need a hi-viz jacket?"
The same reasoning applies to transponders. Keep the big boys in controlled airspace and leave us others alone outside!
I have had a few close calls in my microlight with GA pilots, but mode-S won't change that, as neither they nor I will fit TCAS until that becomes mandatory in a few more years to come.
Uncontrolled airspace is just that - uncontrolled, and those of us who freely fly in it accept the risks that without a good lookout, there is a chance of hitting or being hit by something. Mode-S won't change that.
I accept that if I want to transit controlled airspace, I should have a means of making my aircraft clearly 'visible' to ATCOs and other aircraft. I am fitting a Mode-C for that purpose of this summer's excursion. It's surprising how cheap they are now!
When all controllers have the benefit of using Mode-S surveillance capabilities, there may be some argument only if they can improve services outside controlled airspace. Until then, it's just the 'nanny' state spoiling peoples fun!
And as for the 'majority' of the population wanting to fly abroad in the big cans, I can think of more who will fight controlled airspace expansion using the 'green' argument!