The first question that comes to my mind is, "What the fuck is the point of 2 Gbps service for residential customers?"
Your question is limited to existing technologies and platforms that are built around the assumption of 12/3Mbps connections at best.
Imagine a respectable percentage (or large enough market) where the network was reliably 2Gbps or more.
If the latency were low enough, there'd be less reason not to share multiple GB files on remote drives for editing locally, like agencies using Photoshop files between 700MB and 1GB large.
Hi quality VR conferencing might materialize if the machines connected to each other could exchange data at rates that today are considered too fast to do anything with.
Or what about existing or yet-to-exist distributed networks that might benefit from truly massive throughput? What would be possible with faster interconnectivity across great physical distances? Say 10Gbps. 100Gbps? 1Tbps? 2Exa bps?
Sure, none of those speeds even mean anything today let alone would be feasible in the current market, but hopefully you get my point, which is that the as-yet uncreated future technologies that would evolve and flourish under much faster and reliable Internet throughput can't be known in advance.
And like any resource rich ecosystem, you can bet that once those resources are there, someone and something will use them.
Yeah it'll be used for higher fidelity porn, more unwanted spam, and larger cat videos. But such a network will also be used for cool things like better medicine, more accurate physics, and more efficient manufacturing, in addition to stuff we can't know about yet.
Stop holding back the future by asking for comparisons from today.