I think it’s more of an ease of use issue. When I was in grad school, I used to cycle my work between dev on a MacBook and heavy processing work on a desktop. This was 2011/2012.

Dropbox helped here. They had a Linux client and a Mac client and kept both in sync.

Mine was somewhat of a niche use case. I think every one who cycled between Linux and Mac for their daily work back then thought - yeah I can definitely use those tools but an automatic sync would be nice.

What Dropbox didn’t have was a moat that comes with android or iOS. I use iCloud now since my need to move between different devices doesn’t exist anymore.