### 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)

ERR_FAIL_COND(multimesh->mesh.is_null());
	AABB aabb;
	AABB mesh_aabb = mesh_get_aabb(multimesh->mesh);
	for (int i = 0; i < p_instances; i++) {
		const float *data = p_data + multimesh->stride_cache * i;
		Transform3D t;
		if (multimesh->xform_format == RS::MULTIMESH_TRANSFORM_3D) {
			t.basis.rows[0][0] = data[0];
			t.basis.rows[0][1] = data[1];
			t.basis.rows[0][2] = data[2];
			t.origin.x = data[3];
			t.basis.rows[1][0] = data[4];
			t.basis.rows[1][1] = data[5];
			t.basis.rows[1][2] = data[6];
			t.origin.y = data[7];
			t.basis.rows[2][0] = data[8];
			t.basis.rows[2][1] = data[9];
			t.basis.rows[2][2] = data[10];
			t.origin.z = data[11];
		} else {
			t.basis.rows[0][0] = data[0];
			t.basis.rows[0][1] = data[1];
			t.origin.x = data[3];
			t.basis.rows[1][0] = data[4];
			t.basis.rows[1][1] = data[5];
			t.origin.y = data[7];
		}
		if (i == 0) {
			aabb = t.xform(mesh_aabb);
		} else {