Google Ads has introduced a measurement tool called Cross-Media Reach, first spotted in July 2023, that allows advertisers to measure deduplicated, on-target reach and frequency across video campaigns on YouTube and TV.
Cross-Media Reach aggregates reach and frequency metrics, providing a comprehensive view of brand campaigns and enabling better planning and optimization.
Advertisers can generate reports for YouTube Video Reach and Video View Campaigns, and, in selected countries, include TV metrics from third-party data sources, compare YouTube to TV, making it easier to track and improve advertising investments.
You can find it under Goals > Measurement > Cross-Media Reach.
For more information, read the official announcement here: Introducing Cross Media Reach.