Despite moving hundreds of thousands of miles per hour, why do stars appear fixed in constellations over human lifetimes?

Their incomprehensible distance makes the slight angular change in position negligible over human timescales.

Stars are indeed moving through space at tremendous velocities, sometimes reaching hundreds of thousands of miles per hour. However, this motion results in a change in their angular position relative to the observer only over extremely long periods, spanning thousands of years. Because these stars are so incredibly far away, the small angular shift that occurs during the span of a human life, or even several human lifetimes, is too minuscule to be perceived, leading to the illusion that the constellations like Orion maintain a stable, unchanging backdrop.