The explanation I usually hear for Rey playing an equally, if not more, dramatic role in defeating Palpatine compared to Anakin's (while still not formally replacing him as the Chosen One) is that the prophecy referred only to a single, temporary event, one that could be repeated any number of times. I can't help but raise two objections; why is the prophecy centuries old if its events will be overshadowed in a few decades, and why is Anakin alone the chosen one when it seems a new drama will open with every generation?
My question is whether we (fans, theorists) can ever get this to make sense, or whether we have to accept that this is just an incredibly poor improvisation that Disney has had to make due to an acute paucity of creative inputs.
I'm not the most knowledgeable when it comes to Disney lore, so I'd be really glad if this question was discovered by someone with background knowledge about 1) the prophecy and 2) the post-IX future, if any.
To any layman, it would seem as if the Chosen One should provide the foundations for a new Jedi Order and a long-lasting, peaceful Republic. Anakin's legacy here seems to be hesitantly and underwhelmingly portrayed. This may sound like a personal opinion, but I'm genuinely curious why things ended up this way, and what they plan to make out of it.