Without more context, it's difficult to say for sure what Sarah Bergbreiter meant by "there's still a long way to go." However, in general, this phrase is often used to mean that although some progress has been made, there is still much work to be done. It suggests that the current situation or achievement is not yet good enough or complete, and that more effort or time is needed to reach a desired goal.
In the context of robotics, Bergbreiter may be referring to the fact that although micro-robots have made significant advances in recent years, there are still many challenges that need to be overcome before they can be widely used in practical applications. These challenges could include things like improving their durability, increasing their power efficiency, and making them more reliable in complex environments. By saying that "there's still a long way to go," Bergbreiter may be emphasizing the need for continued research and development in this field.