The primary problem is that they sacrificed the history, meaning and ultimately the "magic" of Arda, all for the sake of shallow pandering.
The strength of Tolkien's work in the third age is the belief that despite their various backgrounds, men, elves and dwarves can put aside differences and come together for the greater good... This does NOT occur in the Rings of Power, because everyone is homogenized and mixed from the outset.
Further detracting from the experience is the degradation of the source material in favor of what amounts to fan-fiction. Legendary characters are intentionally diminished in order to prop up shallow original characters, or for the sake of pushing a blatant political narrative.