If there is a new framework or tool to know about every few months and you change job every three, you will be spending all your time re-learning some strange new wheel and taking energy away from truly excelling at your current tool set.
On top of that, if we chase the carrot of technology we will always be using tools that are less than a few years old. In otherwords, un-tested by time and immature code bases without useful ecosystems and best practices.
RiotJS for example, there is a way it's designed to be used, and it is idealogicaly sound. But also naive. That way will evolve a lot over time as even just a small project revealed a dozen or so pain points to solve, that haven't yet been addressed by the community.
But working on an older codebase, communities have usually solved a lot of those problems with process or ammendments, and there is a wealth of information available.
If you're going for consulting gigs, no problem: Focus on selling solutions rather than specifics. Then afterwards offer up a solution based on new tech, and offer up a better alternative and explain how it solves their problems better.
Many companies don't bother one cannot use the very latest fad, but you can demonstrate proficiency in soft skills, for example.