Actually, one is NOT allowed to move to the left lane to let another driver merge (not "insert")

You must drive on the right
Unless rules or signs allow you not to do so

Letting another driver merge, is NOT a reason / exception to allow this
It happens often, it is seen as courteous , but from a legal standpoint ... nothing allows it

Yes. The colors are changed.
May the driver of the RED car.....

I suppose that the purple car is the one with the "L" on top (blue is closer to purple than red, at least to me). I do not understand the question or which one is the purple car, the only way for this to make sense is that the question is about the red car.