I suspect this is someone at IMDB jumping the gun. They know that Netflix is working on a series of Narnia movies and since The Magician's Nephew is listed as the first book nowadays, they assumed that's the one they're adapting. If Netflix had officially announced it, I'm sure Narniaweb would have done a story about it. 

There has been that rumour for years, ever since the second Walden was released. I think anyone could have posted it  having read the ideas others shared.

@Lewishimself Narniaweb has been the best place for news on Narnia films, for the last 20 years.

IMDb has always been overly aggressive with posting pages on their website. They had an MN page up way back in the Walden days (Walden wanted to make MN after VDT). What I don't know is if they took it back down once Walden was out or if this is the page you found?
IMDb also had a Silver Chair page up for a while when Joe Johnston was going to direct, I haven't looked lately to see if that one ever was taken down or not. 

So it's POSSIBLE that they put a new page up and that's what Ms. Gerwig is writing and directing first? But without having IMDbPro access to see the details, I can't say for sure, and even then I'd want another much more reliable source to confirm the news. 

But thanks for sharing @Lewishimself !! We appreciate you dropping by and posting about it. Certainly worth keeping an eye on.

@fantasia There appear to be two separate listings on IMDB. This one and then another called Untitled Netflix/Chronicles of Narnia TV Movie.  

This can often happen when a project is in development for a long time with very little new information, as the  people who work on it will often make new pages, and then IMDB will haphazardly try to combine them. 

Interestingly, the Magician's Nephew one has a much longer list of status updates (again, I can only assume this is a result of multiple different pages being combined).

However, the two most recent updates (2019, and 2022) are listed as 'Treatments' aka the document that lays out a summary of the movie's entire planned plot beat for beat shown to the executives, before the first draft is allowed to be written. Further proof of multiple changes in direction during the long gestation period?