The point seems to be you could now use any system you wanted (as long as there is a compliant browser) and not worry if your needed app is supported or has all

The point seems to be you could now use any system you wanted (as long as there is a compliant browser) and not worry if your needed app is supported or has all the features of the Windows/OSX version. This lets you take advantage of whatever benefits your desired system provides you without a change of user experience.