Let me explain: Cameras nowadays have evolved and are packed with sensors, such as a light sensor and a suitable shooting conditions sensor. For example, on my S23U, when I take a photo with a 200-megapixel lens, the lens selects the appropriate settings for the image and makes the photo 180, 150, or 120 megapixels. This is a feature, so don't worry; there are circumstances that make the photo shoot at full resolution.
