“you’ll create ambassadors who can help promote DevOps elsewhere in the organization”
This is why people fill DevOps roles. The people who inhabit those roles generally steward others by creating tools, processes and documentation that enables others to do exactly what you’re describing.
The question isn’t whether or not DevOps is a role, that comes down to the state of your codebase, staff, and company.
If it was common for developers to have the latitude to solve these problems for themselves, I’m sure many would. It just isn’t common, and I’m guessing you already know that.