Running a website with comments and "social" elements became much harder the longer time went on, can't really blame them for shutting it down.
I for one am glad they removed that. When I visit a database of information, all I want to see is lists of that information. I dont care what other people think of the thing I am looking up, social media is the place for discussing that.
User reviews is 98% of the reason I went on IMDB. For metadata purposes, Wikipedia and other sources are more convenient.
If you want user reviews go to Rotten Tomatoes or Metacritic, you know actual community review sites instead of a database.