This is true, but only because none of the systems have critical mass. It'd only need a couple of car manufacturers to agree on a system like this for their gps and it'd take over pretty quick.
And it's rubbish for memorizing or entering quickly based on what you've heard over the phone. So much so that almost nobody I know uses it for gps in cars, they all use rather inaccurate zip codes or addresses that require a huge database on device, are fiddly to enter, are awkward to keep up to date and are very inaccurate.
