Any computer that can:

• output video to your connected screen
• can interface with the peripherals of your choice
• can run 24/7 without overheating

Can be used for the creation of animated videos.

You can use a 15 year old Core2Quad processor with an appropriate motherboard and enough disk space to store your scene, with an ATI Radeon 4650 GPU, or even the onboard GPU if you wish.

You can use a Raspberry Pi 5 to make your animated videos. Just use GIMP or Krita to make the still pictures and ffmpeg to render the video.

I’m not an expert, but I think that people who are will need to know more details about what kind of animated video you’re trying to create. In other words, potato-level animations can probably be done with potato-level hardware, while Pixar-level animations will require super high-end hardware. I would say that as a basic guideline, if your PC can play games with animation of the quality level you’re looking for, it can probably create those animations as well.

As a starting point, you would do well to review Blender’s hardware requirements.

Edit: PS: Another major detail to provide is whether you are asking about 2D animations or 3D animations. The requirements for 3D animations tend to be much higher than those for 2D.