Due to my origins, I suffered racism in Europe all my life. I think I have a good experience with it.
I don't think UAE is a racist contry at all. Just go to Satwa and see the mix of cultures. Travel to Oman and you will see even more obvious mixes.
I agree with the focus on classes.
Racism comes with hate. I don't feel any hate towards foreigners, except maybe towards those not able to respect a minimum of local culture, getting drunk and noisy in public places (it's still an arabic country, and not temple bar...).
You can find simple workers to top managers coming from India, Pakistan, Philippines etc...but i agree with the idea of abused low classes.
(the same one that are dying while trying to reach European boundaries).