Feel sorta bad for YTers who make their living off videos but this was just a quickening of the problem thats coming: advertising online doesn't seem very smart, and i think big advertisers are starting to realize their brand, products, etc have probably a negative impact with random advertising on random google adsense, Youtube, twitch, etc rather than a positive one.
It just means the market has to adapt and shift, thats all. You need to depend more on product placement, partnerships, working directly with sponsors, and of course patreons / paid subs / donations / etc rather than passively hoping you make money just putting out content and random advertising paying for your content. Specifically for Call of Duty content, the market is pretty specific and thinks like energy drinks, gaming peripherals, fast food, etc are all good candidates for partnered advertising but just random stuff isn't.
Its interesting that all of this has had virtually no impact on twitch streamers, since they don't really depend on ad revenue at all but instead on subs, donations, and partnerships.