> the cost per GB is shockingly cheap

Huh? We're talking about the same S3 right? At list pricing, 1TB is $23/TB to store for one month, and about $90/TB (plus request fees) to send it out to the internet.

While hard drive prices are roughly 3x what they were a year ago, the price per TB of a new hard disk averages around $30/TB -- assume 2x overhead for other hardware and extra space for parity etc, a disk pays for itself in less than 3 months and lasts 5 years or more.

If you assume it takes 1 month to download that 1TB (about 3Mb/s) that's $29.16/Mbps. When I first started buying internet transit in Europe back in 2008 I think I was paying under $10/month. It's now under $0.10/Mbps pretty much anywhere in the US or Europe at the big datacenters.

None of the "big" object storage services are cheap. They're somewhat reasonable if you only access the data from within the same region, but absolutely insane if you ever want to ship that data outside of that cloud vendor (or to another region etc). The pricing of storage and egress has not changed in a decade (I believe AWS last lowered the price of either in 2016) and in fact it costs even more now due to things like NAT Gateways etc.

It's definitely not "shockingly cheap". It's just cheaper than $80/TB of gp3 or $45/TB of st1, and while sc1 is $15/TB it has a baseline performance of only 12 MB/s. There's quite a few companies out there that have $6/TB/month object storage plans with similar performance, rising to about $15-$18/TB/month for SSD backed storage with far lower latency figures.

AWS have found the ideal captive market: computer engineers who don't know how computers work or how much they should cost.

Whatever AWS is selling you - except Deep Archive - I'll figure out a way to sell you for half that price, if you want, and it'll still be 80% profit for me. Your only downside will be that I don't know what I'm doing so it might not be reliable - but neither is AWS.