Advertising costs money to produce, and the vast majority of paid Linux distro users, such as Red Hat, SUSE, etc., are business/enterprise users, who usually wouldn’t rely on advertising through TV, YouTube, and so on to find enterprise computing solutions. It would be a disconnect between the ad platform and the primary target market.
IMO the title of “worst computer tech company” is essentially a tie between MS and Google right now, with the two constantly one-upping the other back and forth on stupid ideas and corporate practices.