Please read again the excerpt that I provided from that article, repeated below:
You can use Apple USB power adapters for iPad and Mac notebooks to charge iPhone, iPod, Apple Watch, AirPods, and other Apple products.
Apple doesn't have an 10W or 12W Mac power adapters.
And the article is not very well worded.
No Apple device will draw more power than it is designed for. Using a larger power adapter will not harm any Apple device.
If still in doubt, see the following from Fast charge your iPhone - Apple Support
You can fast charge your iPhone 8 and later up to 50 percent battery in around 30 minutes.1
Fast charging works when you use an Apple USB-C to Lightning cable and one of these adapters:
- Apple 18W, 20W,2 29W, 30W, 61W, 87W, or 96W USB-C Power Adapter
- A comparable third-party USB-C power adapter that supports USB Power Delivery (USB-PD)