For serious deep-sky imaging, which component of an astrophotography setup is described as the most critical gear for accurately tracking the sky's rotation?

The equatorial or computerized mount

In the pursuit of astrophotography, particularly for capturing long exposures of faint objects like nebulae or galaxies, the mount component is deemed paramount. The equatorial or computerized mount is specifically identified as the most critical piece of equipment because its primary function is the precise tracking of the celestial sphere's movement. Accurate tracking is essential to counteract the apparent motion of the stars across the field of view during extended exposure times, thus preventing star trailing artifacts in the final image. While the telescope/optical tube gathers the light and the camera captures it, the mount dictates the precision necessary for successful long-exposure imaging.