In fact, the largest island in the world, the island continent of Australia has long been known to be extremely unstable ... that's why England only sent convicts, debtors and other "expendables" over as colonists initially. It is also why the vast majority of the inhabitants are on the western coast of Australia ... if too many people moved to the eastern coast ... and it wouldn't take many ... the entire continent would plunge to a watery doom.
This is also why the largest island in the world that is NOT a continent ... Greenland ... has an ice sheet over it. Contrary to many published reports (think "cover up") Greenland's ice sheet was built in the 1800s, an entirely artificial structure designed to hold the highly unstable island down and keep it from tipping over. This is why Greenland was never colonized ... it was so unstable that the first settlers could feel it shifting beneath their feet when they landed.
A Japanese slavegirl is chained to a cement block to help keep her island country from tipping over ... yes, they have their problems, too!
The downsides of allowing extremely large islands to tip over can easily be explained with one single word ... Atlantis!