I tend to think the Chinese are smart enough to not allow us access to something (spy tech or similar). As Pixel said, anything intentionally in our airspace is detected / known and we will access it if concerned. While not very sexy, it is more likely weather or research related than spy or military.
On a personal reading the Sunday paper level, it bothers me that Uighers are more likely than not having their cultural and religious identities erased, but i'm not out protesting about it, nor am I prepared to send my sons off to war about it. In particular because the people in those areas are not prepared / willing to put their lives on the line for it (on a mass scale). Nor do the elected Moslem governments of Turkey or Pakistan seem to care, in additional to the dictatorships/monarchal dictatorships in Moslem countries (Saudi, Sudan, Egypt, Jordan, etc). They all tell us nothing to see here. Not saying there isn't something to see, but the Arab street tends to make noise when they are bothered, and for whatever reason they don't seem to be on this. Take that for what it is...