Against that accumulation of wreckage one needs to appreciate the sheer size of the U.S. GA activity.
It is at least one order of magnitude bigger than the UK, which in turn is an order of magnitude (or more) bigger than much of Europe.
It is completely normal to fly from say UK to say Crete, crossing southern UK, Belgium, Germany, Austria, Italy, Slovenia, Croatia, Montenegro, Albania, Greece and see 1 or 2 GA planes at the UK end, and absolutely zilch (except contrails at FL300+) the rest of the way. And virtually no "apparently GA" traffic on the radio, too.
The USA also has loads of serious terrain, whereas the UK has almost none except a few "hills" in Scotland and up there there is very little GA anyway.
So for every pl0nker in the UK who gets himself splattered into terrain, having launched into OVC010CB +TRSAGS and winds of XXX/050G075 or whatever (having evidently never read the metars or tafs, and possibly would not have understood them anyway) there will be a dozen doing the same thing in the USA.
Here is one, doing it in a plane rather similar to mine.
Despite all that, the U.S. accident rate, per hour flown, and to the limited extent one has stats available, seems to be better than that of the UK. Probably largely because of their much more accessible IR, which enables any pilot willing to do reasonable due diligence on the wx, relative to his aircraft capability, to fly much more safely.