I think it makes everything taste the same in an intense but uninteresting way, to be honest. It gives it the bad Chinese restaurant quality. Quantity matters, obviously.
I read a comment years ago about a chef who stays that msg makes water taste like soup. So yeah, it improves the taste, but not in a good way. It's similar to drinking tea with a cup of sugar mixed in. msg isn't as bad as sugar when normalizing on how much people consume, but it's still used as a replacemment for good food.