I suppose I should have phrased that slightly kinder, and that’s on me. What I mean is that you can’t take your average jogger and expect them to win the 100 meter dash at the Olympics, no matter how much training and resources you provide them. Is that a real problem? No it certainly is not.
Lots of people like rock climbing but you can’t expect an average climber to win a major competition or climb some of the toughest mountains. It doesn’t mean they shouldn’t enjoy climbing, but if they start training like they are about to free solo El Capitan they are very likely to get seriously hurt.
Average developed, operators, sec. people can do plenty of good work. But put them in a position that will require them to be doing things way out of their area of expertise and no matter how you structure that role and what tools you give them you are setting them up for failure.
Another thing I was thinking about was not individual people being average but rather organizations: an average mediocre organization cannot reliable expect excellence even out of its excellent employees. The environment just isn’t set up for success. I am sure most people here are familiar with having talented people working in an organization that decided to poorly adopt Agile because it’s the thing that will fix everything.