It is a very well written article. The interface of any product is very very vital. A good interface — need not be extremely artistic or beautiful, but it must make using the software or hardware easy.
Even there is great scope for improvement in so called easy to use service like Facebook, it is not easy to try and retrieve a post that you made years ago.
While youngsters and people below 50 find smartphones easy to use, a few hours ago I met a gentlemen aged 70 who is struggling to use the interface of Android OS.
We see older people having difficulty in composing and sending SMS. If someone wants a technology product or service directed at individuals. He must make the interface so easy that it can be used by old people as well. If they are able to use it then anyone can.