That’s a common topic of discussion, see for instance New kanjis added to wanikani or 叶 and other N1 kanji
There doesn’t appear to be any publicized plan to add more levels to WK.
My personal opinion is that adding more levels to WK without changing the way the SRS is implemented and allowing more flexibility wouldn’t necessarily be a good idea because you’ll be taught low-frequency kanji that you may or may not need in practice, and you’ll still regularly encounter non-jouyou kanji in the wild that won’t be on the website. On top of that only a tiny minority of users make it to level 60 currently, so that’s content that very few people would ever see.
That being said I’d certainly prefer more levels with the remaining jouyou kanji over the current kana vocab push… But I see why it makes more sense for Tofugu to go in that direction.