Of course I’m not arguing what Tolkien literally intended as there is no way for You or Me to know where he was pulling from when he didn’t mention it, for all we know when referring to Dwarfs being based on Jews he only had brown Jews in mind and they were never suppose to be white given that he never once mentioned there skin tones, there is literally no way to tell what he would have wanted so it’s all left up to Interruption.
Nor do we have any way of knowing if he would give a toss one way or another if elf’s hobbits or any other none human race/characters were portrayed by none white actors given that as you said they aren’t suppose to line up with real life groups and he rarely mentioned there skin tones and never gives such a divide as he did the humans in the setting.