But apart from that most of the information is quite good as a historic reference.
Each article contains extraordinary insight and is thus a valuable thing to read, especially if you are new to the subject.. as students and industrialists alike.
Even if its 'only of 3 years ago', actually the subject of software and robotics is decades old and has had its ebbs and waves of 'hot new idea of today' such that the subject is very dense.
In my opinion, robotics and autonomous systems is a subject now moderately impervious to the "not the new new" syndrome suffered by technologies, young and old. 3 years is just a blip.
Not true; at the writing of the article, the Pixhawk board was using the LPC2148, and today it uses the STM32F427... who knows what else has been changed over the years as well?
But that's really besides the point, the CPUs they were using have not really turned obsolete like GP said. Even the STM32 F4 series you mention was released in 2011, before this article was written. And that's the latest generation of the STM32 series, so it hasn't gone obsolete.