Pretty sure the parent comment was more meaning "go up a higher level of dimension", so to escape a "3d" sphere they'd point out you could probably do it from a(ny?) higher-than-third dimension.

justinclift is right. The goal is to try to escape from a circle which is still a circle in 3D space. A 2D being may not be aware of the third dimension and might think it's impossible to escape it. Yet it is possible if they find a way to travel in the third dimension.

This is just an analogy anyway. My main point is, or what I hope science can figure out is whether the speed of light is a true limitation of reality or just a limitation of our own perception/understanding