An Uno Q is like $60. So what % are you gonna save on the whole project by using a Chinese knockoff?
Chinese clones of Arduinos are normally between 3x-6x cheaper, and if your project uses dozens or hundreds or thousands of them, especially in developing countries, that's a major price delta.
A lot. The official uno r3 is around $30 while the clone can be as cheap as $5.
Which does not sound much, but to someone living in less developed country, that matters a lot