Why can the Chinese not play cricket?

Whether or not cricket is popular in a country has nothing to do with how economically developed it is. Cricket was invented in Britain and was spread by English colonists around the world during the 19th-20th centuries, so most of the countries where it's a top sport in terms of popularity are former colonies/part of the UK. It doesn't seem to have spread much beyond the British Empire, except in the Caribbean.

As far as Japan is concerned, it never was a British colony to begin with, and was closed to most outside contact until the mid 19th century. Baseball, the American sport that has many similarities to cricket, is very popular though. It was introduced by an enthusiastic American teacher called Horace Wilson in 1871, and became a popular college and high school sport within a few years. Nowadays it's a major professional and school sport (high school baseball in Japan is almost a religion). Maybe the Brits just didn't have the cricket equivalent of Horace Wilson to spread the word in Japan.