I'll elaborate: human error is not all reducible to a UX problem, at least not in any meaningful sense in casting blame at AWS here for causing the user's error. Giving users an explanation of their actions at the top of the page is not particularly bad UX, it seems adequate. If course they could do more, modals that say "here's your estimated costs for the action you're taking" and that might be better. But then again that might not be practical across the range of AWS modules, and a user that if ignores their bills and bank statements for most of a year might easily ignore those notices as well.
If you define every mistake a user makes as a UX problem then you've defined it broadly enough that it loses meaning. I doubt that's you're overall intent, but in claiming the user's failure to read the top of the page was a UX problem you're crossing over into that territory.
I might be more sympathetic if the user wasn't so lacking in awareness that they also didn't read their bills and bank statements for so many months, and didn't take the hour of time upfront that was ultimately necessary to understand part of a massively complex system. No reasonable level of UX design would have fixed all of that.
It's also a bit ambiguous-- it seems to be focused on how it will change the settings and last modified date. I could see how one could read that as "this action will create a copy of your files [and then delete the old ones] rather than moving them directly", warning you that your file metadata will be impacted.
There's also the problem that these warnings are everywhere in AWS console so you develop a bit of blindness to them.
So they have a pretty much wrong button name ("Edit Storage Class" --> "Copy to a different storage class") with an ambiguous warning message commingled with a bunch of other warning messages. I'd call that bad UX.
That being said, 8 months is too long for this bill to be considered AWS' fault. and the fact that he's been working really hard on his movie is irrelevant and comes off as whiny
Plus the following. UX is the umbrella term for "User Experience", not User Interface.
Therefore I'm not defining UX as users making mistakes. I'm defining UX as the user's motivations, journey, and actual experience with the site (and possibly extending to their interactions with the support team). This is not an 'overly broad definition', this is THE definition of UX.
If anything, what's happening here is the reverse. People are defending AWS' bad user experience, by narrowing down the definition to the narrow scope of UI-design and safety-nets. However, no amount of UI safety netting will salvage a website with bad UX (or rather, where UX never came into play during the design stage, except at the very late stages when it was only down to designing a UI).
So to reiterate. I'm not blaming AWS for the user's effective failure to read a technical warning message which then caused them harm. I'm blaming AWS for the fact that it even came to that in the first place. That is bad UX.
Also user experience follows pretty heavily from UI design, you cannot separate the two without losing something. But "experience" is also much more subjective: Some might have a bad experience digging through menus while another person might have a good experience, like the way it's all organized. As an example, I found the notification for this issue perfectly acceptable: it let the user know a copy would be made. That is a pretty clear indication that the originals will still exist, and new ones would end up in Glacier. My experience there would be fine.
User experience is unhelpful in this respect because you cannot design your system to satisfy the experience of every user.
If it doesn't operate like Dropbox under the hood, don't make it look like Dropbox in your interface.
If an action creates a copy of objects, call it "Copy Objects" or whatever.
I think that presenting an S3 bucket as a set of files that you can select and perform operations on sets up false expectations here. And not showing incomplete multipart uploads in the file listing or having any way to see they are there isn't great.
