Sure but what Keynote does is pretty niche. On the other hand, Pages is nowhere near the capabilities of Word and still not a good layout program either. Numbers is OK only if your spreadsheet needs are very basic and you mostly care about the presentation of it. Its performance is so bad that even Google sheet feels better (it's way more capable nowadays, in any case).

Apple have those things only to say they have them and pretend that they have "solutions" instead of having to rely on 3rd party. But they are not really competitive outside of the most basic need and in my opinion their existence is not worth all that much in today's landscape where both Microsoft and Google basic offering are free.

Keynote thrives because Apple does their in-person stage presentations using it.

They need something to handle that... and because it's Apple they won't use PowerPoint.