Final answer:
Modern telescopes have allowed us to see galaxies over 13 billion light-years away, but the first galaxies remain elusive due to their faintness and great distances, making only the brightest few accessible for detailed study.
Step-by-step explanation:
The reason why the first galaxies that formed have not yet been observed by astronomers can be attributed to a combination of factors related to technology and the inherent properties of these ancient galaxies. Specifically, telescopes and astronomical instruments today are indeed very advanced, with the Hubble Space Telescope and other ground-based telescopes having taken extremely long exposure images that allow us to observe very faint, very distant galaxies. While it's true that these modern telescopes can detect galaxies that are over 13 billion light-years away, the very first galaxies still pose a challenge due to their great distances and faint appearances. As a result, even with the most sensitive detectors, we can only obtain spectra and detailed views for the brightest of these distant galaxies, which constitute a mere fraction of what exists.