Dick

To answer your original question, no we don't need music critics any more than we need any other sort of critic.

However, they exist and are good or bad depending on what you expect from them and what they actually deliver.

People must decide for themselves what value to put on their views.

Your plea for objectivity is no doubt heartfelt, but in the absence of both objective criteria for reviewers and, more problematically, objective criteria for musical worth it seems a vain hope.