This article highlights a number of problems that have been facing the Russian Navy since the end of the Cold War. The four floating pontoons this beast tells me that she was likely in a sinking condition anyway and this boat is hardly unique in that respect. Quite a few of their boats have sunk at the pier and some of them are nukes.
Very simply, they just don't have the industrial capacity to deal with all the hulls that have been decommissioned. I expect things will get a lot worse befor they get better too. They've got a long way to go to clean up this mess.
Yeah...a large part of their old fleet is as well. I was stunned when an old Project 58 "Kynda" class cruiser was brought back for use as a flagship just a few years ago. As out of date as this class was, it probably wasn't useful for much of anything else and couldn't have been in very good shape.
While a lot of these ships are still legally in commission, it's doubtful that most will ever put to sea again. It's all they can do to keep modern units going because of poor funding and maintainance...to say nothing of keeping them from burning and sinking at the pier!