Why does everyone praise the acting so?

I don't get it. To me it feels like I'm watching a play, the acting is just sooo theatrical (with some exceptions). Which is fine in a theatre, but on tv it just feels really unnatural to me. The child actors are almost uniformly terrible by modern standards, except for the boy who plays Claudius.
I guess it's just because of the time it was made. The writing is very good at least.