@prabhakar_deosthali, that's true but we are only starting to scratch the surface of the IoT ecosystem, and most devices only transmitt a few kbytes of data.
Using IPV6 and a combination of 3G/4G/5G networks can support the connectivity. Bandwidth problems are occurring because heavy use of multimedia applications on mobile devices, something it didn't happen until a few years ago.
True! IPV6 will solve the problem of unique adddresses to the devices .
But what about the bandwidth requirements.
Assuming we allow free flow trafic between all the devices world wide over the internet of things , the bandwidth requirements of routers,swicthes and all those intermediataries will increase many thousand times . The wwwhole internet infrastructure will need an overhaul.