I know lots of advertisers think they can't live without it --- because promoters have told them so.
As a thought experiment, let's go back to the time when the internet existed, adds existed, but targeted adds were in their infancy. Now let's imagine they were launched as some sort of op-in Google BETA this in early 0s fashion.
Assuming, for a moment that the targeting quality was on part — would that have been a success? Ie. would the user adoption have been significantly higher Apple's Tracking Transparancy Policy? (Considering that consent was involved before distrust accumulated in the following decades as result of forcefully surveiling, fingerprinting, third-party cookiea, facebook shenanigans, appstore malware, supercookies, etc.)