It's mobile devices not having user-facing files as first-class citizens. The mobile era started just as Dropbox started to solve a computer era problem. Bad timing.
I'd argue Dropbox became as big as they are thanks to mobile taking off.
In a computer only world there are myriads of other solutions, elegant or not.
Most work computers were permanently plugged into network shared folders, and would have over the VPN access for on the road salesmen etc.
Home users mostly didn't care about cloud storage or shareable folders, those who did could get away with ftp (basically supported everywhere, like straight in explorer windows)
Dropbox flourished because most people got a second device, always connected, but with no decent file management. Many of us used Dropbox not even for sync but just to properly handle files.
So it's not just me. I'm glad, I feel weird that I have to save links to every Google doc and every internal confluence page because there's no proper search across these.
Especially in a filesystem I know where I placed something, but not always the title, so even if the search function was ok, which it mostly isn't, having to know the wording used for the title is really inconvenient.
Is this still the case? I have a "Files" app on my iPhone that shows me files and folders stored on my device, I can save/load files from most apps (that have a concept of files) and it's even integrated with iCloud so when I save a file to my phone's Downloads, I can access it from my Mac (and vice-versa).
I don't know about Android but on iOS I feel like we've had a simple and ubiquitous user-facing file system for a while. I use it all the time.
I suppose it might not be top of mind for most users because it wasn't there for so long.
Android literally has the Linux file system, although without root only the "home" directory is accessible. But within there is a Downloads folder, Documents folder, and all the other folders you'd expect from a home directory
With root you have access to the entire linux-style system directory
In a computer only world there are myriads of other solutions, elegant or not.
Most work computers were permanently plugged into network shared folders, and would have over the VPN access for on the road salesmen etc.
Home users mostly didn't care about cloud storage or shareable folders, those who did could get away with ftp (basically supported everywhere, like straight in explorer windows)
Dropbox flourished because most people got a second device, always connected, but with no decent file management. Many of us used Dropbox not even for sync but just to properly handle files.