Shader error in 'Nature/Terrain/Standard': maximum ps_5_0 sampler register index (16) on Android

I'm getting the following errors while trying to build for Android on 2021.3.2f1

Code (CSharp):

1. Shader error in 'Nature/Terrain/Standard': maximum ps_5_0 sampler register index (16) exceeded at Files/Unity/Hub/Editor/2021.3.2f1/Editor/Data/CGIncludes/TerrainSplatmapCommon.cginc(62) (on gles3)
2.  
3. Compiling Subshader: 0, Pass: FORWARD, Vertex program with DIRECTIONAL DIRLIGHTMAP_COMBINED DYNAMICLIGHTMAP_ON INSTANCING_ON LIGHTMAP_ON SHADOWS_SCREEN SHADOWS_SHADOWMASK _ALPHATEST_ON _NORMALMAP
4. Platform defines: SHADER_API_GLES30 SHADER_API_MOBILE UNITY_COLORSPACE_GAMMA UNITY_ENABLE_REFLECTION_BUFFERS UNITY_FRAMEBUFFER_FETCH_AVAILABLE UNITY_HARDWARE_TIER1 UNITY_LIGHTMAP_DLDR_ENCODING UNITY_NO_CUBEMAP_ARRAY UNITY_NO_DXT5nm UNITY_NO_FULL_STANDARD_SHADER UNITY_NO_RGBM UNITY_NO_SCREENSPACE_SHADOWS UNITY_PASS_FORWARDBASE UNITY_PBS_USE_BRDF3
5. Disabled keywords: FOG_EXP FOG_EXP2 FOG_LINEAR LIGHTMAP_SHADOW_MIXING LIGHTPROBE_SH UNITY_ASTC_NORMALMAP_ENCODING UNITY_ENABLE_DETAIL_NORMALMAP UNITY_ENABLE_NATIVE_SHADOW_LOOKUPS UNITY_HALF_PRECISION_FRAGMENT_SHADER_REGISTERS UNITY_HARDWARE_TIER2 UNITY_HARDWARE_TIER3 UNITY_LIGHTMAP_FULL_HDR UNITY_LIGHTMAP_RGBM_ENCODING UNITY_LIGHT_PROBE_PROXY_VOLUME UNITY_METAL_SHADOWS_USE_POINT_FILTERING UNITY_PBS_USE_BRDF1 UNITY_PBS_USE_BRDF2 UNITY_PRETRANSFORM_TO_DISPLAY_ORIENTATION UNITY_SPECCUBE_BLENDING UNITY_SPECCUBE_BOX_PROJECTION UNITY_UNIFIED_SHADER_PRECISION_MODEL UNITY_USE_DITHER_MASK_FOR_ALPHABLENDED_SHADOWS UNITY_VIRTUAL_TEXTURING VERTEXLIGHT_ON
6.  

Code (CSharp):

1. Shader error in 'Hidden/TerrainEngine/Splatmap/Standard-AddPass': maximum ps_5_0 sampler register index (16) exceeded at Files/Unity/Hub/Editor/2021.3.2f1/Editor/Data/CGIncludes/TerrainSplatmapCommon.cginc(62) (on gles3)
2.  
3. Compiling Subshader: 0, Pass: FORWARD, Vertex program with DIRECTIONAL DIRLIGHTMAP_COMBINED DYNAMICLIGHTMAP_ON INSTANCING_ON LIGHTMAP_ON SHADOWS_SCREEN SHADOWS_SHADOWMASK _ALPHATEST_ON _NORMALMAP
4. Platform defines: SHADER_API_GLES30 SHADER_API_MOBILE UNITY_COLORSPACE_GAMMA UNITY_ENABLE_REFLECTION_BUFFERS UNITY_FRAMEBUFFER_FETCH_AVAILABLE UNITY_HARDWARE_TIER1 UNITY_LIGHTMAP_DLDR_ENCODING UNITY_NO_CUBEMAP_ARRAY UNITY_NO_DXT5nm UNITY_NO_FULL_STANDARD_SHADER UNITY_NO_RGBM UNITY_NO_SCREENSPACE_SHADOWS UNITY_PASS_FORWARDBASE UNITY_PBS_USE_BRDF3
5. Disabled keywords: FOG_EXP FOG_EXP2 FOG_LINEAR LIGHTMAP_SHADOW_MIXING LIGHTPROBE_SH UNITY_ASTC_NORMALMAP_ENCODING UNITY_ENABLE_DETAIL_NORMALMAP UNITY_ENABLE_NATIVE_SHADOW_LOOKUPS UNITY_HALF_PRECISION_FRAGMENT_SHADER_REGISTERS UNITY_HARDWARE_TIER2 UNITY_HARDWARE_TIER3 UNITY_LIGHTMAP_FULL_HDR UNITY_LIGHTMAP_RGBM_ENCODING UNITY_LIGHT_PROBE_PROXY_VOLUME UNITY_METAL_SHADOWS_USE_POINT_FILTERING UNITY_PBS_USE_BRDF1 UNITY_PBS_USE_BRDF2 UNITY_PRETRANSFORM_TO_DISPLAY_ORIENTATION UNITY_SPECCUBE_BLENDING UNITY_SPECCUBE_BOX_PROJECTION UNITY_UNIFIED_SHADER_PRECISION_MODEL UNITY_USE_DITHER_MASK_FOR_ALPHABLENDED_SHADOWS UNITY_VIRTUAL_TEXTURING VERTEXLIGHT_ON
6.  

I'm using 2021.3.2f1 and it's a brand new, flat terrain made using this version. Here are my build settings:



What is the problem here and how can it be solved?