In fact, both are true. It just depends on where you live.
What he said is the case within the European Union due to some EU law regarding warranties. I believe in the EU an extended warranty like AppleCare only goes into effect after the original warranty has expired. There are also statutory warranty periods of a year (I think) for devices like the iPhone.
In the United States, on the other hand, AppleCare replaces the original warranty rather than adds onto it.
As you say there could be some legal jiggerypokery but Apple claim it's still only two years for an iPhone:
> Up to 2 years from date of purchase for Apple TV, iPad, iPhone, iPod, Apple Watch or Apple Watch Sport
With the price of iDevices rising there's probably a "reasonability" court case brewing where someone argues that a £1200 iPhone X should last longer than 1/2 years.
What he said is the case within the European Union due to some EU law regarding warranties. I believe in the EU an extended warranty like AppleCare only goes into effect after the original warranty has expired. There are also statutory warranty periods of a year (I think) for devices like the iPhone.
In the United States, on the other hand, AppleCare replaces the original warranty rather than adds onto it.
Here's a page describing AppleCare within the UK: https://www.apple.com/uk/legal/statutory-warranty/, which lasts for three years instead of the two within the United States.