I assume this blog is a re-hash of the JDEC retention standards[1].

The more interesting thing to note from those standards is that the required retention period differs between "Client" and "Enterprise" category.

Enterprise category only has power-off retention requirement of 3 months.

Client category has power-off retention requirement of 1 year.

Of course there are two sides to every story...

Enterprise category standard has a power-on active use of 24 hours/day, but Client category only intended for 8 hours/day.

As with many things in tech.... its up to the user to pick which side they compromise on.

[1]https://files.futurememorystorage.com/proceedings/2011/20110...