To be honest, I'm inclined to ignore what YouTube says there. While yes, you want to focus more on a good title and thumbnail, search is still a huge part of YouTube. You shouldn't focus 100% on keywords, but they definitely help.
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The blue graph is my search impressions. I changed the keywords to something much more targeted at the start of 2020... They changed the algorithms at the end of 2018 as you can see with the flatline. Back in those days, single word tags would get you by fine. 2018 onwords, the algroithm changed so you can't rely on single word tags, and look what happened with the blue line when I changed my single word tags into proper keywords. Everything got a boost.
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Another video where I changed my keywords around March 2020...
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again, another example of fixing up my tags and keywords.
When YouTube says stuff like this, I don't always think they know what they're talking about. They've made a LOT of poor choices over the last 6 years indicating that they don't always get it. They're the second largest search platform, OWNED BY THE BIGGEST search platform... So saying search terms and tags aren't important, to me, feels a bit misleading on their part.
If they completely eliminate tags completely, then so be it, but you can't argue with data. I put the theory of good keywords into practice, and the impression data doesn't lie.
Learn to read your analytics, learn to read your impressions data. I mean, heck, YouTube had a horrible comment system right up until 2019, so I'm less likely to agree with what they say.