Any web service could "go at any time", in fact, the smaller players are more likely to fold up shop, not give advanced warning, and not offer something like Google Takeout. It's happened before. Some smaller players in the past didn't even have good backups, and simply lost user data. You could self-host, but again, unless you want to put a lot of labor and money into reliability and security, you can also lose.
I'd call the reasoning used in this article "Reader Derangement Syndrome".
I seriously don't understand the logic behind this whole article. Is he really afraid of the google play store disappearing? Is he aware that you can install an apk from anywhere after changing one setting? Virtually everything that's been shut down by Google has had a graceful shutdown where you could export your data in a calm manner.
It sounds like he's more concerned about the NSA stuff than having services shut down but never really says that. It's just a weird rant as far as I can tell.
I'd call the reasoning used in this article "Reader Derangement Syndrome".