100% agree with this. The point is to have one team working together, where the team has all the required dev, ops, and security skills, or access to tools that can augment the team's skills.
Each member of the team does not need to be a superhero, they just need to be jointly responsible.
The question is how your partition your organisation. Classic is something like Development | Testing | Production. DevOps wants to integrate the different department, but you cannot build one huge team of 100 people.
You could partition by product instead Gmail | Search | Maps | etc.
You could do both partitions, which gives you Matrix Management [0]. In the software world this is more commonly known as introducing the role of a product manager in addition to a team manager.
Just to clarify, that's how I run it here but I've been told by some fairly respected devops people that it's not really devops. But in general I agree.
Each member of the team does not need to be a superhero, they just need to be jointly responsible.