I would not trust those metrics you showed. Its almost impossible to get real numbers. But one fact is certain, wordpress is almost the entirety of PHP out ther

I would not trust those metrics you showed. Its almost impossible to get real numbers. But one fact is certain, wordpress is almost the entirety of PHP out there. Facebook tried to patch PHP twice, first with HHVM, then with Hack. Finally they gave up and announced Hack will be "its own language" because they were so fed up with the inconsistencies. Slack is really just a chat. A glorified, slow version of IRC. I would not boast it as a marvel of engineering. If you want to se how to build a good and scalable chat system? See Whatsapp. Dont get me wrong, PHP is still used, and will be after 10-20 years. But the fact reamins that is on a slow decline. Its never going to be as popular as it was back in the early 2000s.