It is lol. When your shareholders barely fidget to your announcement that you've been throttling older model phones, but respond when it's reported you've slashed iPhone X targets by 40%, it matters. Investors have historically been bullish on Apple's prospects, and it's not the magnitude of the drop that matters but the fact it happened.
I'm not kidding anyone, Reuters is not that kind of media outlet. Their revenue doesn't come from getting clicks on their website via advertising, it comes from other outlets picking up their stories, pictures, and videos. They are explicitly value neutral and for the most part, people picking up their stories are going to change the titles and edit the wording. When Reuters says, "Apple slashes sales targets for iPhone X according to sources", there is nothing clickbait about it, the title is the story and there's nothing else to it. Clickbait is when you say something interesting but don't elaborate (in order to encourage people to click on the link, or in the past, buy the newspaper), or when you twist the truth to make something sound more sensational than it actually is. Neither is true in this case.
The problem isn't China, the problem is Apple isn't selling as many phones as they think they ought to be. The market in China is part of the problem, but it's not as if the problem is contained to emerging markets. The Chinese luxury goods market really isn't all that different from North America and Europe. You have inward pressure in China to buy domestically designed phones, but even stronger pressure to have the product that will convey the most prestige. This levies the same impact that wanting the latest gadgets/technology does in NA/Europe, they just conceive of it differently. Again, Apple's issue isn't demise, the issue is stagnation. If I'm an Apple board member, and I've experienced significant gains for essentially the past 15 years, I am disappointed and frustrated by two straight years of slashed targets for my most important product.