Read the OP more closely, identity not about the vestigial fluff you are talking about.Class identity is subjective. It's how we perceive the class.
They can't force a class identity on us.
Yes wotc can very much do that by way of how the class mechanics are designed and written. Fluff and lore are not identity. The only way that would change as you describe is if a player or gm rewrote the class entirely into an entirely new class with an identity that didn't involve being a subclass of a different class.
Next started experimenting with a sorcerer that was very much more focused on gaining traits from their bloodline & such at one point but ultimately went with "wizard but hot" as crawford says