He says it’s not a known defect.
Ok, a little bit of a rant here. Apple recently announced a repair program for the iPhone X to address a problem where the screen becomes unresponsive. Googling "iphone x unresponsive" yields a vague array of results, with a few of them consisting of users having this problem, but nothing that would indicate an epidemic. Yet it apparently has been deemed severe enough so as to warrant a special repair program.
On the other hand, Google "ipad pro 10.5 white spot" (or bright spot), and the results appear to point to a much more defined and widespread issue, with many posts here, on reddit, Apple's own forum, and other places describing this EXACT problem. How is it possibly not a "known issue"?
My theory... the iPhone X issue is fixable, the iPad Pro 10.5 issue is not. The iPhone X problem is described as being the result of a faulty part, which can be replaced. But the iPad Pro 10.5's white spot disease is presumably caused by a design flaw, a part under the screen that, after a period of time, interferes with the backlighting, with perhaps manufacturing variances explaining why some have this problem and others don't.
So, unless we can somehow exert more pressure on Apple by bringing more attention to this, I suspect they are going to just try to sweep it under the rug.