The link is broken, and I'm not sure we want this
paragraph in there, as it's somewhat speculative
(we don't know how extensively Slack uses PHP any
more, nor do we know how much of a factor it is in
any security issues) and is probably mostly
preaching to the choir. The "bounty" link should
suffice.
While from my anecdotal experience, it is accurate that at many SaaS
providers, dozens or even hundreds of engineers have access to
production infrastructure, the "essentially all" statement isn't true
(not sure how that got added), and in any case, there aren't great
public sources we can cite to educate folks who might think Silicon
Valley startup practices are better than they actually are.