I’m not being sarcastic. Apple did not invent the smartphone because smartphones existed before the iPhone (as you acknowledge in your post). They made a really good line of smartphones.
The only way you could think they invented the category is if you don’t know what invent means.
At that point, you might as well make a "nothing ever gets invented" argument.
Previous smartphones were essentially iterations of PDA with an added cellular modem. Which was also a category Apple had spearheaded, with the Newton.
The iPhone completely changed the product category and continues to define it to this day.
By your logic, the car also wasn't invented because carriages existed before; they just required horses.