A Bill Harvey Consulting (BHC) and Fox study of $2.2 trillion in sales in relation to $48 billion in ad spend by media types found that ROAS of Premium digital video is higher than television, and the synergy between them adds a kicker effect. That study, and Nielsen NCS, both find that Premium digital video and TV have about twice the ROAS of Nonpremium digital video and digital display.
The average person can tell you that it makes sense to expect more positive effect with your ad in Premium digital video versus a Skip-in-5 environment, however advertising practitioners, closer to the trees, have not been quick to definitively confirm and act upon that notion, and have instead raced to the bottom in terms of that great oversimplification called CPM. Global ad dollars in digital are double TV; digital being 90% small space static ads with documented lowest ROAS among major media types. Up until the end of 2020, the growth (after Search) has always been in Nonpremium or Display. Now more marketers have woken up and the idea of Television plus Premium OTT is starting to spread exponentially.