Ramy wrote:

I think short of something like FLARM, the only thing which could have
prevented this would have been better situational awareness of which other
giders were working in the same area.

I can only support this. Looking out is the first thing to do. But FLARM
really can help to save your day (maybe your life). I had a near miss
yesterday. FLARM did indicate traffic right of my course. Still not seeing
the other glider, I did a left turn. In the same moment the other glider
passed me in a distance of maybe two wingspans.

These little boxes really work. Everyone who can afford a glider of some
1000 $ or ? can also afford another some 100.
Chris