Facebook is issuing a warning to Audience Network advertisers that with the coming of iOS 14 and the user privacy settings that come with it, will heavily impact the effectiveness of advertisements. There are thoughts that it will completely make them ineffective in some cases.
According to Facebook:
“For developers and publishers using Audience Network, our ability to deliver targeted ads on iOS 14 will be limited. As a result, some iOS 14 users may not see any ads from Audience Network, while others may still see ads from us, but they’ll be less relevant. Because of advertisers’ reduced ability to accurately target and measure their campaigns, app developers and publishers should expect lower CPMs on Audience Network and likely other ad networks on iOS.”