The Queen is an iconic, remarkable figure in today's progressive world. There are not many representative monarchies left and she is the symbol of that system and Britain in general. She has been around for the longest time, even people of older age remember her as the Queen, she is a part of their everyday life. Her death will cause an uproar of the century.
Because she has held this high post of Queen of England for so long, her death will most certainly be an event of historic proportions. Likely, her legacy will be remembered and featured on every news outlet for some weeks and even months after her death. As a figure of England, this would not be surprising in the least.
The death of the Queen of England will be an important event due to the long history of her reign. She has ruled during some important times, such as world wars and social changes. After a long life, her death will not be a surprising story or landmark news events of the decade.
No, Queen's eventual death will not be the news story of the decade. Throughout 2016 alone, many famous people have passed away, including Muhammad Ali and Prince. Death of celebrities, especially now, are common, inevitable, and absolutely to be expected. No celebrity death, as far as I'm concerned, has the potential to be the "news story of the decade."