YouTube's copyright system keeps a more aggressive watch on music content, and many gaming videos using licensed themes are almost certain to be blocked. YouTube's match content system redirects revenue for identified videos using unauthorized music to source, but the author can simply block viewing around the world or certain territories.
But then there is the heaviest punishment, called Strikes, when the injured person considers the use of his content to be serious, in which case, according to YouTube policies, a channel that receives three strikes will be deleted.
It is within this latter context that Nintendo will have chased YouTube channels dedicated exclusively to sharing (and monetizing) the songs of the best-known games in its historical catalog, from the Super Mario Bros. series, The Legend of Zelda, Super Smash Bros, as the VG247 advances. The "drop of water" will have emerged due to the sharing of the soundtrack of the recent Fire Emblem: Three Houses, which encouraged Nintendo not only to block the songs from this game, but from other first party titles.
One of the channels that saw your bulk videos removed was GilvaSunner who saw dozens of blocked themes. The channel, which has 342,000 subscribers, currently lists videos older than one year. But the channel BrawlBRSTMs3 will have received the maximum and closed punishment, specializing in uploading music videos in 30-minute looping.
Remember that Nintendo has always taken protective measures of its intellectual property, not allowing its flagship series to be monetized on YouTube until last November, when it decided to release the content, and thus encourage creators to produce videos of the your games, no copyright issues.