Reviewers have been expressing their own personal views on the subject at hand for probably as long as there have been reviews.

Here's a description of George Bernard Shaw as theatre critic:

"But Shaw truly began to make his mark when he was recruited by Frank Harris to the Saturday Review as theatre critic (1895–98); in that position he used all his wit and polemical powers in a campaign to displace the artificialities and hypocrisies of the Victorian stage with a theatre of vital ideas."