Because it removes textures, it often runs smoother than heavy mods. Why Players Use X-Ray Packs
Several X-Ray resource packs are popular among Minecraft players, each offering slightly different features: resource pack x-ray
Most modern servers (Paper/Spigot) use "anti-xray" plugins. These turn hidden ores into "fake" ores that only turn real when you are directly touching them. To an X-Ray user, the world just looks like a confusing mess of fake ores. Because it removes textures, it often runs smoother