Should the image be uploaded at 300 DPI in AI generative content?

Raster images are resolution-dependent (height x width in pixels).  Use the highest resolution that your AI service offers.  In most cases, you'll need a paid plan to access more advanced features.  Don't worry about PPI.  It's baked in to your resolution by default.

High-res rasters ≥ 4800 x 3600 pixels contain more, small-sized pixels per inch.  This provides greater details.  Low-res images ≤ 2000 x 1083 contain fewer, large-sized pixels per inch which can augment fuzziness or images that look pixelated.

When shopping for Stock images, I always opt for the highest resolution possible. If I need a smaller image later, I can always downsize it in Photoshop.  However, the reverse isn't always possible.

Enter math-based vector graphics. Vectors are resolution-independent. Vectors are made up of paths, such as lines, squares, or shapes. Because they are not made of pixels, vector graphics can be scaled up or down without quality loss. But you should designate a PPI that's commensurate with how the vector graphic will be used.

PPI for Vectors:

• 72-96 PPI: This is common for on-screen projects, but it might not look as crisp on newer high-density/Retina displays.  Think small computer icons.
  

• 150 PPI: This is the recommended value for most digital & web use now. 
  

• 300 PPI: This is a good option for printed materials. It's also the standard DPI for a high-quality print finish. 
   

Hope that helps.

Hello,

Just to clarify - DPI = Dots Per Inch. which refers to printing - how many dots there are in a square inch.

PPI - Pixels Per Inch = how many pixels there are in an image.

These values become more relevant when printing.

Pixels Per Inch & Pixel Density | What is PPI Resolution? | Adobe

Regardless of what dpi you use, the file has to be a minimum of 4MP in size. A 96 or 72 dpi image will not meet that criteria, so it will need to be enlarged. I only upload AI and I do so at 300 dpi (approximately 24"x13.5"). One way or another, you will have to use a decent upscaler. I uploaded a 36"x36" image at 72 dpi successfully. If I were to purchase that image and I needed a 300 dpi version of it, it would be a little larger than 8"x8". I'm not sure myself if the image is converted to 300 dpi during the upload process. Someone else might be able to answer that.