[Zachery]

You either are not active in those communities, or you're wearing some rose tinted glasses.

vBulletin 3, (3.0.x) had a lot of early security issues
phpbb2/3 had a HUGE swath of security issues years back
IP has had their own security issues.
Even XF has had at least one security issue in a non beta release.

Things happen, how you react to them is what is important.

I won't argue that we should take better steps to enforce better security. I know the last thing anyone of the devs want with 5 is an issue they need to work on for security. We hate the issues just as much as you do.