At least according to the page you linked, the Pen has a caveat of “Sold Separately” so I’m inclined to think the article is correct or the Microsoft page needs better copy?
Perhaps they mean “also available separately”.
For example go to the Tech Specs tab and the pen has footnote 3: “Sold separately”
Yeah the site feels like an e-shop from a decade ago. Every section scrolls in a different direction, with multiple different ways of representing the same information.
I disagree on the Magic Keyboard being too expensive. Many of the cheaper keyboards you can get for the iPad are too heavy, have keys that are too sticky, or both. The new Magic Keyboard is very light, very well constructed and has a keyboard that resembles typing on a Mac, which is no small feat IMO.
The Surface Pro flex keyboard weighs 340 g including pen. The Magic Keyboard for iPad 13 M4 weights over 670 g. That's quite heavy. Nearly double without added weight from the Pencil Pro.
It costs a bit less than buying Apple's $350 Magic Keyboard for the iPad Pro 13 along with a $130 Pencil Pro. https://www.apple.com/shop/ipad/accessories
Both of these are way too expensive.