Apple was absolutely moving to USB on iPhone, just not as fast as some would have liked. The fact of the matter is when switching from 30-Pin to Lightening, Apple promised that Lightening would be the port for the next 10 years, and got raked over the coals by customers who thought moving from 30-Pin to Lightening was nothing more than a money grab. That was a transition to a significantly better port, Lightening to USB-C was a sideways move for most customers. Most users don't want new cables; my mother-in-law held off on upgrading to a new USB-C iPhone for like two years because she didn't want to have to change cables all over her house and car.
It made sense switching the iPad and Mac over first. iPad is much more of a computer than a phone is, and needs things like fast data transfer and compatibility with keyboards and other peripherals. I'd be shocked if more than 2% of iPhone users use the port for anything more than charging.
And now we're stuck with USB-C for all eternity now because no one has any incentive to develop a better port if it can't be used in Europe; once again proving the EU is completely unable to think through the actual end results of its regulations. "Let's freeze innovation because we're impatient". They should let the free market do its thing and leave hardware and software design to the professionals. We've already had phones limited in size by the USB-C port. And the regulation hasn't even been in place two years. And when Apple eventually releases a portless phone because it is physically impossible to fit a USB-C port in the phone, people on MacRumors will scream "malicious compliance" and "They're just trying to sell MagSafe pucks and AirPods". Well, why does anyone think Apple will spend the money to invent a "micro-USB-C" port if they can't put it on phones in Europe?
You know what the EU said about Micro-USB when they tried to force everyone to use that abomination of a port? "It's unlikely a better solution will come along soon." Why is everyone so convinced they are right about that now even though they were wrong about it ten years ago. The free market was working - we saw tons of people on MacRumors saying “I’ll never buy another phone without USB-C”. That’s how it’s supposed to work! Vote with your wallet. Don’t get regulators to come in and freeze innovation because you’re impatient.