Redditor u/Stickybeebae posted their concerns in the r/LOTR_on_Prime subreddit, saying, “Given how general audiences and even some Tolkien fans are less familiar with the ‘Silmarillion’ and events of the second age, I wonder how many aspects of the show will be true to the lore and assumed to be fabricated by the show runners [sic]. Quite a few people seem taken aback by the cult of Morgoth for instance or Galadriel’s Amazonian disposition, both online and friends in real life who have only read the trilogy.”
In summary, their concern is that fans will see canonically accurate events or character portrayals and deem them incorrect since they’re not one-to-one with the original film trilogy. When someone with limited information sees something that doesn’t align with that info, they can either expand their research or double down on their ignorance, and u/Stickybeebae’s fear is that fans will opt for the latter choice before “The Rings of Power” is even released.
Take the concerns with Galadriel, for instance, originally played by Cate Blanchett. A younger Morfydd Clark gives her life in “The Rings of Power” because, canonically, Galadriel has been hanging around Middle-earth for a really, really, really long time. In the earlier days, she was less peaceful and more aggressive, more war-minded. She had to be — “The Silmarillion” depicts a vicious series of wars that grossly overshadow the events of “The Lord of the Rings.”