Their would be no real audio, and no lots of other things. There are real costs to waiting for more bandwidth. The development of many new applications that need the bandwidth is deterred. We think this is a big deal. The major barrier to deployment of ISDN, the here and now digital technology, is the high consumer price.
Lets consider the following.
Bell Atlantic and other firms used ISDN to provide business voice services that would compete with feature rich PBX services. In Japan and many EU countries, residential ISDN is priced relatively close to POTS prices. I was in Japan in August of 1996. NTT distributes literature which provides the names and contact information of ISPs providing ISDN connections to the Internet. NTT officials told me in August they wanted to double the number of ISDN lines by the end of 1996.