Stop being an expert in something, and instead learn how to learn, and execute. Aim to become a polyglot (or even a polymorph!), and go with the flow, rather than spending all your time focusing on what's currently cool.

There is tremendous amount of value in working with people who can jump in and out of projects, with the associated cost. But more than that, it also helps you bring a different approach to problem solving, one gleaned from turning the problem over in multiple ways. This is an adjunct to critical thinking.