An intranet today can simplify, cut costs, provide easy and cheaper expansion. And it could ensure valueable information is in the hands of the right people when they need it. By definition, they are not centralized. And that is a huge exposure to the different operating systems and configurations of each and every user. And the system requirements to run can cause costly hardware upgrades.
Remote access can be it's own problem and cost center.
By contrast, an intranet application can be centralized. An upgrade of the application on the server is immediately enjoyed by all users. System requirement is the ability to run a modern web browser, and LAN or web access. And one user can merrily run a MAC in a sea of Windows PCs. Microsoft Certified Professional.