### 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)

gui[0] = v.x;
				gui[1] = v.y;
				gui[2] = v.z;
				gui[3] = v.w;
			}
		} break;
		case ShaderLanguage::TYPE_MAT2: {
			float *gui = (float *)data;
			if (p_array_size > 0) {
				const PackedFloat32Array &a = value;
				int s = a.size();
				for (int i = 0, j = 0; i < p_array_size * 4; i += 4, j += 8) {
					if (i + 3 < s) {
						gui[j] = a[i];
						gui[j + 1] = a[i + 1];
						gui[j + 4] = a[i + 2];
						gui[j + 5] = a[i + 3];
					} else {
						gui[j] = 1;
						gui[j + 1] = 0;
						gui[j + 4] = 0;
						gui[j + 5] = 1;
					}
					gui[j + 2] = 0; 
					gui[j + 3] = 0; 
					gui[j + 6] = 0; 
					gui[j + 7] = 0; 
				}
			} else {
				Transform2D v = value;