Yes, the animals do emote.

Rating: 9/10 (19 July 2019)

First off- I will address that most of the negative user reviews pre-date the American release. All these all users from countries that released first or are they like other movies where negative reviews are made without seeing the film?

I gave this film a 9/10 because it was not perfect. It was excellent however. When you review a movie, you need to rid yourself of any prejudice. This is hard to do with a remake, but it is possible. The only reason I gave it 9 instead of 10 were a couple moments that took my mind away from the world they created. One was a visual and the other was a singing. I will not get specific as I don't want to give the reader any prejudice.
This film opens with an updated version of the powerful opening from the original animated movie and moves on from there. Many of the scenes are similar but updated to be more representative of how it would actually look in reality. The "I just can't wait to be King" is one of the most notable indications of this.
The animals do emote. They show emotions in the same way our domestic animals or animals in a documentary film would. Do characters not have cartoon waterfall tears? No, but they do indicate sadness the way real animals would. Their eyes do show expressions of love, anger, sadness, fear, hatred, etc, and so does their body language. It's just more subtle as it would be in reality.
The musical numbers are very well done with some changes along the way. They are not shot for shot or even lyric for lyric remakes. But, they do add to the emotions of the movie. Those that say they come out of nowhere need to rewatch Enchanted where "live action" musical numbers vs animated musical numbers is joked about. They do not distract, so they are woven into the film accurately.
The voice talent does a great job. There is humor among the hyenas with some really funny stuff and the adlibs they kept for Timon and Pumbaa are hilarious. They do steal the show in their scenes, but that's what good comic relief always does. Scar oozes off the screen in a different kind of sinister way. He is vile in this retelling. All the voice talent did a great job and I will add that they cast voices with similar tones to the original voices and that even aided in not being distracted by new voices.
The creative team did an amazing job of putting together a realistic retelling of an amazing story that works in all mediums. The changes are mostly for realism and that was the point. One standout scene of this is how Rafiki discovers what truly happened to Simba.
Bottom line: watch this movie for entertainment and you will not be disappointed. If you watch it to only compare or wonder if it was necessary, you may have already made up your mind.