My landscape material have 16 materials in it with their own base color, alpha, roughness, normal and height map.
You need to use texture atlases just like they mention earlier in the thread, or put your textures in less channels, but you’ll never get very good results. With atlases you don’t loose quality.
Right now I have 8x8 textures in my atlas, one for base color and alpha, one for normal and one for roughness and height. So that’s 16 materials but only 3 texture samples.
Nothing prevents you from putting in another atlas to increase it to 32 or even higher.