The bottom line here is that Nike has a new template and they have applied it to pretty much everyone from national sides such as England and France to clubs such as City and Barcelona, none of whom traditionally have the sleeves in a different colour. It won't rob any of toss teams / countries of their identity; whether it will hinder shirt sales is yet to be seen but no doubt Nike will monitor that carefully and you can be sure they will drop the fashion quickly enough if it does. Hopefully, they will change their template regardless.
If you look back over the years, various fashions for football shirts have come and gone; many of which have been horrible. Seems to me that most clubs had their best ever kits in about 1970.