[ronancremin]

The author reaches a trite conclusion uninformed by facts. The user agent string is used by at least 90+% of the Alexa 100 to improve user experience.

There is a silent evidence problem here. Successful use of the user agent string improves the user experience but goes unnoticed; failures are very apparent.

From the article:

"user agent string was a complete mess, and near useless"

vs.

https://etherpad.mozilla.org/uadetection-usecases

His conclusion is a bit like saying "I don't see why I need ABS in this car because I've never skidded since I got it."