There's both a short and long answer to this question.
The short answer is, you'll have to ask Muslims how the treatment of the Uyghurs is affecting them. The answers you will get will be as diverse as the people you ask.
The long answer: Because China is a global superpower with unmatched surveillance capabilities, they have the ability to shape popular opinion in a way other countries are only beginning to realize. The international community was slow on the uptake with the information that Uyghurs were being rounded up into concentration camps. Now that everyone knows and nothing has been done, there is likely a sense among Muslim communities that China and the countries with which it has forged deep ties are not willing to go to bat for them. This shouldn't have been surprising to international people of any faith, as fellow left-wing authoritarian dictatorships in Russia, Asia, and Latin America have often been hostile to believers of any religion.
As far as middle eastern countries go, I'm certain none of them want to get on China's bad side. They may be majority Muslim nations or have religious governments, but their leaders want to maintain power more than they want to stick up for a Chinese ethnic minority that happens to also subscribe to Islam. Challenging China is a fight they would not win, and nobody wants to start WWIII.