Comment by pwg

But, ads directly correspond to revenue stream, and a loss of ad "impressions" would result in a reduced revenue stream, so a "protect the advertising" response is not at all unusual to consider as a portion of their (eBay's) reasoning for this ban.

Given how hard they push sellers to purchase their "extra cost listing enhancements" (i.e., purchase to have your listings show in the "advertisement" spots) it appears that they may make a decent revenue stream from these advertising angles. An AI-agent could find listings without going through the advertising displays and as such cut into this revenue stream.