As a pretty serious hobbyist photo-taking-guy I'm a big fan of smugmug, my "sharing photos with friends and family" photo website (http://gmcbay.com) is hosted with them, but I don't think of them or use them as a good long-term file "storage"/backup solution.

All of the photo-specific type of storage solutions (Google, Amazon, Smugmug, Adobe's CC thing, etc) are kind of flawed for many reasons (some outlined in the OP blogpost) when used as what I think of as "digital negative storage", IMO.

I just store all of my (original, RAW-format) photos/videos on giant harddrives inside my desktop computer and have that backed up automatically and continuously via backblaze. Local storage is ridiculously cheap, and so are offsite automatic backups.

For people who just deal with jpg files from a phone camera or whatever then YMMV and these photo-specific services may be just the thing, but I've yet to try one that doesn't feel like it is getting in your way if your normal workflow is big RAW files with processing via Lightroom/Photoshop, etc.