It is not entirely clear if the author aka Slack chose PHP with these reasons in mind apriori or did they choose PHP first and are now justifying why their choi

It is not entirely clear if the author aka Slack chose PHP with these reasons in mind apriori or did they choose PHP first and are now justifying why their choice of PHP is not bad. I'm going to guess they picked PHP because they knew PHP and not because of the nice reasons mentioned in the article. That is the article should be "why slack is sticking with PHP". Almost all the major languages are actually (despite lots of HN debate and arguments) fairly good choice for developing not because the major languages are expressive/powerful but because they have very very mature tools (e.g. Java sucks but the JVM and its tools are very mature) and lots of people who know it. Basically you could write a plethora of articles with "Taking MAJOR_BORING_LANGUAGE Seriously". For example I'm responsible for choosing Java for my companies startup. Java historically is not a very productive language to pump something out but in recent years it has vastly improved... regardless I chose Java because thats what I knew at the time and I would pick it (or some other JVM language) again. And I could rattle off whole bunch of reasons why the JVM still kicks butt but the reality is I am biased because of my familiarity.