Is it copyright strikes? That's not what the article says.
While the Pokemon bans would arouse suspicion of The Pokemon Company taking action, the Pokemon publisher is not believed to be involved with the bans. Several of the affected content creators, including the previously mentioned PokeRev, have previously worked with The Pokemon Company in an official capacity. Many were even invited as guests to major Pokemon events like the Pokemon World Championships. Neither Instagram nor parent company Meta has commented on the unexpected wave of bans against the Pokemon content creators.
And if you watch the embedded video, his ban message just says "Community Guidelines" and it sounds like nobody has been able to get a straight answer about it. Also, he got his account back automatically after verifying his contact info, and he doesn't know why that worked either because he didn't change anything, while some other people with the same ban message instead received automatic appeal rejections, which is wild because nobody can tell what the difference is between accounts that got auto-reinstated and the ones that got auto-rejected.
There is someone in the Youtube comments claiming that usernames containing Poke, Poki, or Pokemon are getting auto-flagged by a bot, which sort of makes sense (except that it doesn't explain the differing appeal outcomes) and was something he speculated in the video, but they are cagey about their sources so I'm consigning that to Youtube comments rumormill until I see better info.