just look at the insane amount of computers that currently exist and need to communicate to do data processing.
I remember 30 years ago most people used one single computer for the family at home, half of the people i knew didn't have proper internet access. (and this is from a western perspective, the rest of the world was even far less digitized).
Now look at how much networked computers are around you.
- your phone
- one or multiple TV's
- laptops/desktops etc
- smart home appliances.
and this is just looking at the very small sample size of a normal household, add up to that things like the digitizalisation of factories, the digitalization of the rest of the world. (internet access has grown massively in the past 15 years in the developing world).
We have far more computers then a decade ago, and far more people have them aswell, and it shows very little signs of stopping.
IPv6 for instance, supports an absolutely infanthomable IP address space. (which people often seem to think is overkill), but looking at the past growth, i think having suchs a large address space is a wise choice.
Another thing which people seem to not notice is that a lot of older DC's are being phased out, mainly because these facilities are repurposed telephone exchanges and far less suitable for more power hungry computing power.