It seems from comments that Warner are looking to "StarWars-ify" Lord of the Rings. So expect unproven/inexperienced diversity hire writers to invent some woke [word deleted] stories.
Peter Jackson says he wants to be involved as despite the Hobbit debacle he maintains he is the best "custodian" of the Tolkien IP. I suppose if he and his team directly write the stories and control the development of the characters it could work but as Hollywood these days is all about Virtue Signalling first and foremost that is unlikely to happen.
Whoever does it the options for material looks pretty thin. How much actual scope is there for 3rd Age movie length stories that have both a beginning and conclusion within the age and do not impact the events or timeline of the core story or characters?
Meanwhile amazing fantasy stories and worlds from authors like Robin Hobb, Joe Abercrombie, David Gemmell or Brent Weeks are crying out for wider recognition.