What is the explanation for the reported seeming lack of COVID-19 infection in China these days where people are traveling widely, large groups gather regularly, and no extreme social distancing precautions are being enforced?

Here again, this is simply a consequence of the fact this is an unnatural situation. They are keeping the pandemic going in the areas of the world where there have been successive waves of infection through re-spraying areas of concentration where people are gathered in sufficient numbers to get another widespread surge in cases. They have not done that subsequently in China following a very severe first wave because they view China as a kind of secret weapon, as they are wanting to promote a war with the West and don’t want to see China too greatly weakened, because they know it will be easy to subjugate as it is already self-subjugated via the Chinese Communist Party. Whereas the West is more unruly and more of a thorn in the side of the Extraterrestrial Alliance because there is greater freedom and many free-thinking people who cause trouble due to their non-conformity. So again, this is not due to the cleverness of the Chinese regime and brilliance in managing the pandemic through government policy, but simply that the interlopers are giving them a pass for now and concentrating their efforts elsewhere in keeping the pandemic going.