It's almost 2019, and every application that wants to share stuff via "the cloud" must still implement support for each cloud provider separately, even though WebDAV has existed for over a decade.

In other words, "the cloud" is really just a lie told by people trying to trick you into handing over your precious files and locking yourself into their walled garden. If it ain't standards-based and interoperable, it's not "the" anything. It's "a" piece of shit.