I think the addition of Keyword functionality for the iOS version was last addressed in 2019, well before even version 3 for MacOS. With processors now better and more storage space available, I don’t think those two are limitations anymore. Keywords are one of the most versatile elements of Scrivener, and it would be a delight to have them available in the mobile Scrivener. While I can get by without them on mobile, it would be nice to be able to abandon the workaround and just use keywords right there in the mobile app. If it’s too much to be considered, I understand. It would be a very nice thing, indeed, though.