M1 Ultra was never meant to beat the 3090. However, it can certainly keep up with the 3090 BUT only up to a certain wattage. Obviously the 3090 is a beast of a GPU and can pull a lot more wattage. In fact the 3090 can pull more power on its own than the entire M1 Ultra.
Actually, Nvidia GPU is the performance per watt king. 70W mobile Nvidia 3060 is 3x faster than Macbook Pro M1 Max 32GPU and 2x faster than Mac Studio M1 Ultra 64GPU on Blender rendering.
7.23s - Nvidia 3080ti (GPU OptiX Blender Linux Mint 20)
8.21s - Nvidia 3080ti (GPU OptiX Blender Windows 10)
13.13s - Nvidia 3080 mobile (GPU OptiX Blender)
16.39s - Nvidia 3060 70W mobile (GPU OptiX Blender 3.0)
20.57s - AMD 6900xt (GPU HIP Blender 3.0)
29s - 2070 Super (GPU OptiX)
30s - AMD 6800 (GPU HIP Blender 3.1)
34s - M1 Ultra 20CPU 64GPU (GPU Metal Blender 3.1)
37s - M1 Ultra 20CPU 48GPU (GPU Metal Blender 3.1)
42.79s - M1 Max 32GPU (GPU Metal Blender 3.1 alpha)
48s - M1 Max 24GPU (GPU Metal Blender 3.1 alpha + patch)
51s - Nvidia 2070 Super (GPU CUDA)
1m18.34s - M1 Pro 16GPU (GPU Metal Blender 3.1 alpha + patch)
1m35.21s - AMD 5950X (CPU Blender 3.0)
1m43s - M1 Ultra 20CPU 64GPU (CPU Blender 3.1)
1m50s - M1 Ultra 20CPU 48GPU (CPU Blender 3.1)
2m0.04s - Mac Mini M1 (GPU Metal Blender 3.1 alpha + patch)
2m48.03s - MBA M1 7GPU (GPU Metal Blender 3.1 alpha)
3m55.81s - AMD 5800H base clock no-boost and no-PBO overclock (CPU Blender 3.0)
4m11s - M1 Pro (CPU Blender 3.1 alpha)
5m51.06s - MBA M1 (CPU Blender 3.0)