If you just use that space as a flat range, it is almost certainly more than enough. But if you split it up in multiple levels of subnets, you can run into difficulties balancing having enough subnets and having enough space in each subnet.
That will never ever happen. Making 240/4 public will break Amazon (and many others) which do use it privately. The software updates to route it across the net would have been taxing. When making it public was suggested years ago, IETF saw the proposition as encouraging IPv4 and refused to entertain it.
In short: The market has already decided and it's private. It's far from the first time an unofficial arrangement is the de facto standard.
Except for when it doesn't.
If you just use that space as a flat range, it is almost certainly more than enough. But if you split it up in multiple levels of subnets, you can run into difficulties balancing having enough subnets and having enough space in each subnet.