To Reproduce:
On Mac OS 12 open the .AI file from the attachment (NativeIllustratorFilesFRESH.zip) in Adobe Illustrator
Ignore the font warnings, but link the images (ignore links for any images not included in zip file)
See the screenshot (artifact.jpg), notice the artifact lines around many of the images
Now save this AI file as a PDF using the Adobe PDF Preset "Illustrator Default"
Open this PDF in Acrobat and ensure "Smooth Images" in Preferences is enabled
Notice the artifact
Now using Acrobats option "Save AS Opimtized" (and this is the most important part) downsample the images to 300 dpi in this PDF
Look at the resulting PDF, now you will see the artifacts regardless of the smooth images setting on or off. If you output this using the APPE rip the artifacts will render

If you turn off the GPU setting found in "Menu > Illustrator > Preferences > Performance" the artifact disappears from screen. But having this setting off and then creating the PDF doesn't resolve the downsample issue.

On the Windows OS, regardless of GPU setting On or OFF the artifacts never appear. Not in AI, not when images are downsampled or viewed in PDF (regardless of smooth images setting)

Can you fix the MAC version to avoid these artifacts? Basically make the Mac match the Windows behaviour? Especially important is the PDF creation and artifacts appearing after downsampling.

Since this appears to be a public forum, I have not posted the files. Please retrieve the files from Adobe Exchange case: 55198

Other notes:
The downsample issue occurs with other software that downsamples images, suchas Callas Toolbox and Pitstop

Environments:
MAC OS 12:
AI Version: 25.0.1
GPU: Intel Iris Pro OpenGL Engine

Windows 10:
AI Version: 25.4.1
GPU: Intel(R) HD Graphics Family