In general, I don't have a problem if a character is recast as a different color/race/whatever for artistic reasons. However, I really hate the double standard. If you took Disney's The Princess and the Frog and recast the lead as a white person for a live action movie there would be outcry of whitewashing, racism, cultural appropriation, and who knows what else. But going in the other direction is supposed to be fine. At least that's the environment we are currently living in in the U.S. Not sure how it is perceived in other parts of the world.
I don't have too much interest in seeing a live action Little Mermaid. I did see the live action Aladdin and it was pretty good. I really missed Robin Williams as the Genie though. I would prefer that Disney work on creating new classics vs. remaking old ones.
Your last line sums up all what I have to say. it's disrespectful to the original work when major elements are changed when remaking old classics. it would have been better if they could create new classics to match new trends rather than forcing new trends on old ones in the name of "remaking".