No, time dilation is not directly related to deviating from the shortest path through spacetime. Time dilation occurs due to differences in relative velocity or gravitational fields, not specifically because of deviations from the shortest path through spacetime.
In the context of special relativity, time dilation occurs when two observers are moving relative to each other at different velocities. The observer in a relatively faster-moving reference frame will measure time passing more slowly for the observer in the slower-moving frame. This effect is known as "velocity time dilation."
In general relativity, time dilation can also occur in the presence of gravitational fields. In regions with stronger gravitational fields, time appears to pass more slowly when observed from a region with weaker gravity. This effect is known as "gravitational time dilation."
The concept of deviating from the shortest path through spacetime is related to the principle of least action in physics, where particles or objects follow paths that minimize the action. It is not directly tied to time dilation.