No. Skippable video ads are the most common type of ad on YouTube videos. The YouTuber only gets paid if the viewer watches at least 30 seconds of the ad.
Overlay ads and Display ads are ads that appear in small boxes. The YouTuber only gets paid for these if the viewer clicks the ad to expand it.
There are Nonskippable and Bumper ads that play before a video, and viewers aren’t given the option to skip over them. YouTubers tend to get the full amount for these ads, as long as their viewers stick around.