This film is well-made and a lot of fun. If taken too seriously one misses the point. Don't take the premise, the "what if" theory too seriously. Shakespeare likely was the man and author of the plays and poems, as most believe. But the presentation of Shakespeare's England in the film is captivating, as is the depiction of how the stage worked in his time
The acting in "Anonymous" is also superb, and the presentation of an author's love for his work.
Is there any truth in this film? Yes. Shakespeare's work is the greatest writing of his time, or of any time. As Ben Jonson said in the movie, and in history.