We don't actually know that it was "only Wuhan first". SARS-CoV-2 is believed to have spread worldwide as early as November.
Wuhan is the 9th largest city in China and also more "blue collar" than cities like Beijing or Shanghai, so the odds that the most visible outbreak of all would occur in Wuhan by chance alone aren't as low as you think.
Wuhan is the 9th largest city in China and also more "blue collar" than cities like Beijing or Shanghai, so the odds that the most visible outbreak of all would occur in Wuhan by chance alone aren't as low as you think.