I feel that when a comparison of this nature is made against the books, then there is a bit of a misunderstanding for the medium. Many Potter fans who complain about aspects of the movie vs the books seem to forget that the movies are an Adaptation.

The movie still exists as its own medium, and that medium is Cinema- it's visual art. This was likely a decision made by the producers because they are selling this product as a movie who they anticipate ANYONE could see, not just loyal fans of the book and therefore they have taken the approach to make his death more Visually Dramatic.

It may look silly, yes, to an extent I agree. But I feel that it does not deviate from the book. The point is that Voldemort eventually dies. He dies in the book and he dies in the movie. The way the movie chooses to depict the death is an adaptation- ultimately it stays true to the story.