They’ve been an advertising company since 2000, so I’d argue that yes it was there, people just didn’t recognise it/gave them the benefit of the doubt.
Granted, advertising in the early 2000s was vastly different though. It was served organically, with none of the tracking or embedded-scripting nonsense that's ubiquitous today (whether from Google or other actors). The very notion of "ad-blocking" or "tracker-blocking" would have made no sense back then.