This a known bug in Ghostscript 9.54.0 that has already been fixed, but not released yet. For now, you may downgrade GS, or avoid internal use of Ghostscript by running asy like so:
asy -tex pdflatex example.asy
The GS version that comes with TeXLive-21 for the win32 platform has the patch already incorporated. So there, the error does not occur.
It may be due to a bug in your graphics library (or card). Here are some things to try
(I haven't tested the full TL 2021 installation under Windows, only the executable that I submitted):
Remove the now (mostly) obsolete lines
settings.outformat = "pdf";
settings.prc = false;
Do you get an OpenGL image?
What happens when you press the e key?