Because DevOps has effectively joined the Operational and Dev domains, it introduces security dependencies which neither domain had to consider before.
When an org's security personnel carry out threat modeling exercises, they tend to make unconscious assumptions about the efficacy of their own security controls. This is dangerous.
The most common privileged security gaps that attackers exploit come from sacrificing effective privileged admin security on the altar of operational convenience.
If <that one PAM tool everyone uses> was good enough on its own, then no one in banking would get hacked, because they all use it. Clearly there's more to the story.