Interesting, how come there are obviously incorrect pixels ?.
But there’s no promise that they will. The photo feature may be more of an automated speed bump, a way to reduce silly answers and pixel spam, and let people self-select, than an active human moderation tool. Moderating is boring and expensive in time and/or money, why would anyone actually sift through thousands of hand-written pages of arithmetic?
2840 pages. Doesn't seem crazy. Page looks like it was written by hand? Next. At two pages per second it's less than half an hour of work.
If you compare them to nearby "correct" pixels, they usually just have one of the three RGB values that are sharply different.