If they are flying in uncontrolled Class G airspace, then ATControl don't need to be aware of them and actually don't want to have to be aware of them. Awareness -> control -> responsibility -> too much workload.
You might be on to something here. But in this case I have to wonder why that hyperactive product manager / sales honcho had me work several months on it, as that guy has an ATC background.
There can be many speculations, from the positive to the negatice, with cluelessness in the middle
A lot of glider and ultralight people would rather die young than implement safety devices that cost weight, money or complexity.
The lack of all these goodies has a clear consequence on the accident rate (guess why they are compulsory on larger aircraft),
so its a deliberate decision to live with a considerable risk or leave it. I'm fine with that - as long you just kill yourself, and not some
other people. The sheer number of sad glider and ultralight crash casualties per year should be enough to start you thinking, however.