You use the term ethnic cleansing and genocide but that does not actually mean anyone is being killed is it?
Let's assume that the average village was harboring or feeding terrorists even if the average villagers are not militants themselves. How is it less ethical to disband these villages without actually killing anyone compared to actually targeting Burmese government officials with lethal force?
The is the position of the Burmese government is that the targeted villages were doing exactly that.
https://www.thestar.com/news/world/2017/09/19/rohingya-muslims-being-wiped-off-burmas-map.html
Accepting that is true, Burma has killed a few hundred people engaged in open revolt and displaced a large group of people that were helping them.
In the United States helping criminals get you in jail for decades. No one is really trying to refute that.The international community just is concerned that the reaction is to harsh.
Look if this is just international hand wringing then none of this matters. However, if the U.N. intends to actually do something I think it would be best for us to be able to identify exactly why Burma is the bad guy, the locals are the good guy and why we have the moral authority to go into a sovereign country and interfere with internal affairs.