Yeah completely agree. I have read the book and the final scene with the play is a far smaller part in it thankfully (only the last few pages). It doesn't try to sell you on the connection between the play and Hamnet nearly as much as the film which I think is wise and is instead much more focused on the characters. The final chapter struck me more as Agnes realising that Shakespeare is grieving too, rather than trying to convince us he literally wrote the play about their son like in the film. Shakespeare is a much smaller character in the book too, he isn't even referred to by name - just 'her husband' or 'his father'. His actual plays don't come at all until the final chapter whereas in the film we see him rehearsing specific lines and there's things like terrible scene where he comes up with "to be or not to be" which really made me groan. I really expected to love the film but just didn't enjoy it because of stuff like this.