physics people: how accurate is this?

[daijobu]

This is an image from Relativity Visualized by Lewis Epstein, describing the tradeoff between traveling through space and traveling through time. Is this really how it works, or is it an over-simplification?  Is it really just a matter of traveling down the hypotenuse of space vs. time, using the pythagorean theorem?  

link to photo

 

Edited November 29, 2020 by daijobu
photo link

[Not_a_Number]

I can't see any image 😞 

[daijobu]

Thanks for the heads up.  Maybe this link will help.