Optimization of the game. Shadows and others

Hi, I have tested this game on 2 PCs, one with a RTX 4090 and one with a GTX 1070. Both use AMD processors and W10 operating system.

Turning on shadows reduces the FPS tremendously and more if you increase the quality of the shadows.
This is not normal, especially with an RTX 4090.

The bottleneck is due to the GPU and no matter if I lower other settings such as resolution or textures of the players, if instead of putting it to 4K I put it to 1080p remains the same, there is no difference.

What’s wrong? Am I the only one that this happens? Because I have tried it with 2 PCs and I have updated drivers.