Apple has updated its vintage and obsolete list of products to include the iPhone 5 starting from October 30th last month. Apple dropped software support for the iPhone 5 with iOS 11 in 2017 itself, so it makes sense for the company to drop hardware support for the device now.
A vintage product as per Apple is one that has not been manufactured for over 5 years and less than 7 years, while an obsolete product is one that was discontinued over 7 years ago. Once a product is marked obsolete, Apple discontinues all hardware service for it with no exceptions. Apple has marked the iPhone 5 as vintage in the United States and obsolete for the rest of the world.
Apple has a distinction between vintage and obsolete products to comply with local laws of California and Turkey where OEMs are required to support their products for at least two years after marking it obsolete. However, the Turkish laws only mention iPads and Macs which is why Apple has marked the iPhone 5 as obsolete in the country as well.
This means that if you own an iPhone 5 which requires servicing, you will have to take it to an Apple Authorized service center or retail store in California to get official support from Apple. Third-party repair shops will happily repair your old iPhone 5 though and at a cheaper price as well.
Apple continues to support the iPhone 5s with iOS 12 so it is unlikely to be marked as obsolete or vintage anytime soon.
Apple will also mark the Mac Pro (mid-2012), MacBook Air (mid-2012), and 13-inch MacBook Pro (early 2013) as vintage from December 30, 2018.