They want the app to work forever, even if the underlying cloud storage service gets killed.
Hence, being able to transparently transfer your data to another underlying storage service without the app changing at all is what most normal people want.
They want a box saying "This app's storage expires on 20th of April. Please choose where you want to transfer your data without disruption of service (and where it will be hosted from now on): Dropbox, Google Cloud, OneDrive, pDrive, Mega, ..."
I've spoken with a lot of regular folks. They don't care about privacy or self-hosting or decentralization at all. They never will. To them technology is a tool with which they make their lives easier. We should take a page from them. :)
(Although to make it 100% clear, I do care about privacy and anonymity very much; but it shouldn't be idolized and put on a pedestal, otherwise people like me will be made irrelevant with time -- one could argue this has already happened).
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TL;DR: Sites strictly advocating for some tech principles lost most of my vote a while ago. We the techies get too distracted by our own shinies and must make a come-back to pragmatism and serving the regular people. It's OK to code stuff as hobbies but promoting them as universal values gets a "nope" from me. And that comes from a guy who wants to retire at his own house with 3 internet connections, and work on Tor-on-steroids and automatic replication of encrypted data until he dies.