The 100% fake enthusiasm, especially if it comes after buying a mediocre product.
The annoying corporate speak.
The bad voice over where lipsyncing is completely gone, this is mostly a thing of the past here in Sweden, but from time to time you get ads from companies launching a product across europe and only record one video to the ad and then translate and do a new voiceover for specific languages as needed, but fail to sync the audio with the video.
Annoying music, for months now a company has been pushing their financial services withe the same terrible ad that is a slideshow and an increadibly annoying music, there is no person talking, they just have a fast tempo music track. I have vowed to never buy anything from them because their ad sucks and is annoying.
Reusing ads, sometimes a company buys almost all ad slots on YT over months and reuse their one ad video so it is completely grating.
Self-righteousness, some ads go from being overly enthusiastic to being intolerably self-righteous. There was a new clinic chain of companies that started a big push a few years ago on yt and for several months you had to listen to an overly kind and happy grandmother wearing a company branded sweater, faking a hearty laugh and telling people to go to their clinic.
They are guarding the Goa’uld in your basement!