I'm sorry you've had such poor experiences with Enterprise DBAs. It sounds like you're drawing upon your personal experiences to make generalizations about a profession. We all do it, but professionalism requires us to step back from our frustrations and work together for the good of the team/organization/company/purpose.
As an Enterprise DBA, I know I have to be ready to be an SME on any number of topics at a moment's notice. I have to understand my data structures and logical modeling, I have to understand IO patterns and concerns (RAM and physical storage are the ones that crop up the most often for me), I have to understand security, I have to understand networking. I'm sure that you also have to consider many of these things as well so I'm not better than anyone, I'm just doing my job.
On top of that, I also have to make sure that my organization's best interests are considered. So if I'm slow to fulfill your request, or even if I say, "no, I can't do that" please don't take it personally. It's just that there are other things to consider than what you need right now and what you think is what you need to do what you need to do as fast as possible. Some times the "fast and easy" way to do things isn't the correct way to do them. Let's figure out a way to work together to do what needs to be done correctly the first time so that we're not plastered on an HN article that says, "why I moved from MySQL to Mongo to PostgreSQL."