Being in the realm of imagination does not mean that they are not based any kind of physics real or otherwise. For example, swords, shields and knives often are exactly modeled on real world physics, even if they take it beyond that by adding things like magical powers. Being taken seriously doesn't mean following real world physics, it means following whatever rules that are defined within that fictional world, again as seen in modern rules for D&D and MMO combat.
Pro wrestling is actually a very serious form of combat because those throws and slams are real, but what makes them fake is that they are choreographed in advance. And that "sport" of wrestling choreography is taken very seriously, because if you don't do those moves correctly somebody can actually get hurt.
None of that has anything to with why the combat in this show is lackluster, which has more to do with the decisions made for this particular show more than anything else. And the job of fantasy is to make you believe in it and for that to work you have to take it seriously.
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You are repeating yourself again. This show was not the result of any rights given by Tolkien before he died. It does not represent any story he actually wrote and gave rights to covering the second age. He did not intend for the appendices by themselves to be the basis of the story of the 2nd age or anything prior to it. It was intended for the legendarium made up of other works that he had not completed to be the basis of the 2nd age and prior stories. Those works were published after he died and this series does not have the rights to them. It was the Tolkien estate who came up with the idea of creating a television series of more than 8 episodes based on the appendices in 2017, meaning decades after JRR Tolkien had died. So to argue that this convoluted way of assigning the rights to a studio around the story of the 2nd age is what Tolkien intended is blatantly false. That is not what he intended. What he intended was to finish fleshing out the story of the 2nd and prior ages in his legendarium and that those things would be treated as a single consistent continuity from beginning to end. Meaning not something that some studio could just insert their own made up story into that goes against everything else within that larger continuity.
Again, just agree to disagree. There is no point continuing.
We are repeating ourselves.