Really? I can’t think of a single example of this. For example, a Rav4 comes with three engine options but they are all still called a Rav4.
The Rav4 shares the same platform as the Camry, which also has a couple different engine options, but Camrys are all still called Camrys. They are different vehicles with a different consumer demographic.
In fact, your link shows that multiple Toyota models share the same engine. So it isn’t the engine the differentiates the models.
Can you give me some examples where manufactures changes the engine size and also changes the model name?
Actually, scratch that. My point is that car models take a long time to develop. That’s an objective fact. It doesn’t matter how many engines Toyota has, it is still a fact. Even a refresh of an existing model takes a long time and costs a lot of money. Cars are complicated to design and build. That’s the reality.