Embrace mediocrity and find another outlet for your creativity.
This is among the worst advice for programmers I've ever read. And it's pointless advice because it's where the majority of programmers already are.
Oh, I certainly agree that clever code is a bad idea, but you should never stop thinking creatively about how to make your code better. Focus it on finding ways to structure your code that are elegantly simple and obvious, on finding the perfect name for that variable, function or class, one that precisely captures the meaning and intent -- and if there is no such perfect name, focus it on finding ways to refactor your code so that there is a perfect name. Programming -- done right -- is an inherently creative task, and the scope for beneficial creativity is vast.
This even applies at the micro level. It's almost always the case that any handful of lines of code that contains branching logic can be structured in several different ways. Take the time and try each of them! See which is most concise, which is most readable, which highlights one aspect of the logic flow or another... and then spend some time deciding which aspect will be most important for the next programmer to read it. Think about how you can write code a little bit differently to eliminate -- and visibly eliminate -- important classes of functional or security bugs.
One of the more important insights I received, after nearly 20 years as a professional programmer, was that comments are evil. Comments are a hack to work around the failure to write code which is sufficiently clear and expressive (note that I'm talking about inline comments, not comments used to generate documentation). When I find myself typing a comment, I step back and look for ways to improve naming, or refactor, until the comment is no longer necessary.
Those are just a few examples, there are many more. Programming, like any art, is a never-ending opportunity for learning and improvement, because perfection is unachievable. Doesn't mean you shouldn't try, though. I can already hear the complaints "But I don't have time for that crap, I have deadlines, and..." that's just another set of constraints to be optimized. When time is tight, I focus on simplifying and making absolutely sure that my code is bug-free and has thorough automated tests, because there isn't any time for extended debugging.
Never, ever settle for mediocrity. One of my proudest days was when another programmer whose skills and code I highly respect called my code the cleanest and clearest he's ever read. I strive to impress my colleagues (and I work with some of the best) with clarity, simplicity and elegance. Sometimes I succeed, mostly I fail... but I always learn in the process. After 25 years, I think I'm learning more every day now than I did when I started. The lessons are more subtle and far less obvious, but I think they're more valuable.