### Godot version

v4.2.beta1.official [b1371806a]

### System information

Ubuntu 22.04.3 LTS 22.04 - X11 - GLES3 (Compatibility) - AMD Radeon RX 560 Series (polaris11, LLVM 15.0.7, DRM 3.42, 5.15.0-88-generic) () - AMD Ryzen 3 1200 Quad-Core Processor (4 Threads)

### Issue description

![image](https://github.com/godotengine/godot/assets/1330325/7a986599-5a68-42a4-beb1-5d3b4bf7db6b)
![image](https://github.com/godotengine/godot/assets/1330325/e8b8546b-b47b-4add-9567-7f70709ab03c)

Culling 3D goes bellow 60 fps even with just about 50 simple animated models. With v4.2.dev6.official [57a6813bb] many more models can be spawned without fps drop. However, both versions do show high cpu usage for culling 3D. Without animations there's barely any usage.

### Steps to reproduce

Spawn models with animation with the Compatibility renderer.

### Minimal reproduction project

[CullMRP.zip](https://github.com/godotengine/godot/files/13400514/CullMRP.zip)

memdelete_arr(global_shader_uniforms.buffer_values);
	memdelete_arr(global_shader_uniforms.buffer_usage);
	memdelete_arr(global_shader_uniforms.buffer_dirty_regions);
	glDeleteBuffers(1, &global_shader_uniforms.buffer);
	singleton = nullptr;
}
int32_t MaterialStorage::_global_shader_uniform_allocate(uint32_t p_elements) {
	int32_t idx = 0;
	while (idx + p_elements <= global_shader_uniforms.buffer_size) {
		if (global_shader_uniforms.buffer_usage[idx].elements == 0) {
			bool valid = true;
			for (uint32_t i = 1; i < p_elements; i++) {
				if (global_shader_uniforms.buffer_usage[idx + i].elements > 0) {
					valid = false;
					idx += i + global_shader_uniforms.buffer_usage[idx + i].elements;
					break;
				}
			}
			if (!valid) {
				continue; 
			}
			return idx;
		} else {
			idx += global_shader_uniforms.buffer_usage[idx].elements;
		}
	}
	return -1;
}
void MaterialStorage::_global_shader_uniform_store_in_buffer(int32_t p_index, RS::GlobalShaderParameterType p_type, const Variant &p_value) {