How often does your cloud storage provider allows you to send 1Gbps to them ? For the ones I use (dropbox, mega, google drive), the answer is never where I live. At best, it will be 10% of that, and usually less.
I've managed ~400Mbps with Backblaze. OneDrive peaks at 150Mbps (probably more but was limited by my laptop's Wi-Fi). I bet Amazon S3 would also be very fast.
Raising upload speeds would also give an incentive to cloud storage providers to take advantage of them and improve their ingestion speeds.
Inbound is very cheap in DC/cloud. The traffic is pretty asymmetric , lot more outbound than inbound , the connections are not . Your ISP may have peering limitations, or interconnect up stream might be throttling. The 1 Gbps is rated capacity to the NOC not the entire internet
From a decent VPS I have easily hit 1 Gbps with google, Dropbox and OneDrive with rclone configured well.
Raising upload speeds would also give an incentive to cloud storage providers to take advantage of them and improve their ingestion speeds.