To accurately measure the size or location of something requires energy. The more precise the measurement, the more energy is required. The amount of energy required get the precision below the Planck length would literally create a black hole.
Because the uncertainty in the measurement is related to the wavelength of a photon used to make the measurement and smaller wavelengths (higher frequencies) lower that uncertainty but are more energetic.
To accurately measure the size or location of something requires energy. The more precise the measurement, the more energy is required. The amount of energy required get the precision below the Planck length would literally create a black hole.
Why does it require more energy?
Because the uncertainty in the measurement is related to the wavelength of a photon used to make the measurement and smaller wavelengths (higher frequencies) lower that uncertainty but are more energetic.
PBS Spacetime has an excellent video on this very subject.