Very few authors had such a grasp of the English language ever, let alone in his generation. He really was a "once in a millenia" tier writer. You would think other writers would have more respect instead of an overweening desire to rub their crayons on his prose.
It really is a litmus test to see if a writer is worth their salt or not.
And depending on what kind of criticism is leveled, you can usually also tell what shortcomings the author has.
Tolkien excels in worldbuilding, he excels in the use of language, he excels in the use of topoi and themes, he excels in his attention to fine detail and the creation of a large bigger picture.
And to make one thing clear: You don't have to like Tolkien's writing, but as an author, you
must understand its importance, you
must be able to understand what makes it so special, you
must understand its strengths and achievements.
Being an author and not respecting Tolkien for what he did is like being an artist and saying Rembrandt, DaVinci or Dürer are unremarkable.
That is not to say that Tolkien is perfect in every way, but what he did is so good, it has never been surpassed... but that's hardly surprising when you think about it.
LOTR is the culmination of a lifetime of research spanning various topics including religion, history, literature and philosophy. It is the culmination of a lifetime of vastly different experiences, spanning all the joys a human being can feel and the horrors of being a soldier during WW1 that only very few people felt (and lived to tell the tale). It is the culmination of a thought process and creative endeavour spanning decades.
If someone truly wanted to surpass Tolkien, it would have to be a person that dedicated decades of their life in a way that Tolkien did. You simply won't crank out a story and setting as finely crafted as Tolkien's creation without spending a lot of time, effort and dedication.
So it's kinda hilarious to see random dangerhairs trying to take a shot at this material with a show that can be summed up as "Generic fantasy with a double-dose of GoT-style smut and token minorities".
On one hand, you have an author that spent decades of his life to create a vibrant world with an extensive mythology, lingustics and millenia of history... and on the other, you have people who think the height of writing is Harry Potter.