Ihor Radchenko writes:
I am inclined to change ![img](url "caption") to
![caption](url) for links without description (links with description do
not obey caption in org export).
Upon further investigation, I have found that our base MD reference we
follow in ox-md is defining image syntax as the following:
![Alt text](/path/to/img.jpg)
![Alt text](/path/to/img.jpg "Optional title")
https://daringfireball.net/projects/markdown/syntax#img
Therefore, Org mode is doing everything right within the scope of MD
specification we follow. Pandoc does not.