I would agree.

At this sorta level, the "nut behind the stick" is the determining factor IMHO.

Kawa is making less mistakes (oppsss...."fewer mistakes" to satisfy some grammar Nazis), in reality, with a comparable ship and instruments he can use, he would likely be at the top or close to it.
Same for many other pilots.
Since he seems to avoid team flying, and also seems to not like some newer rules and tracking/ground help for others, he seems to fit US rules better.
Shudder to some in the US about US rules.

Some comes down to the type of flying required for the competition site.
Those with eastern US flying may not do as well in the western US mountains. The reverse is also true.

Professional glider contestant? No.
Talented amateur pilot that can afford to do a ton of flying and contests? Yes.

To me, professional means the task generates an income. Kawa does well and can afford the time and entry fees. I doubt he makes any money flying or flying contests.
Yes, he has fun, yes, he gets to fly cool sailplanes that others own, yes, he does well.