I don't think Twitters large engineering teams are just sitting around doing nothing. The article is essentially saying that most of the Twitters resources are

I don't think Twitters large engineering teams are just sitting around doing nothing. The article is essentially saying that most of the Twitters resources are being spent on making it an ad platform as opposed to making it "pulse of the planet" system. So much of the Twitters engineering efforts is invisible to outside world but probably very useful for ad buyers.