The BBC had an article pointing out that Trump has business interests in Egypt, Saudi, and Pakistan, and no business interests in any of the banned countries.

Also, when people talk about 'muslims' in these Anglo countries of ours, they're generally not imagining Indonesians or Malays. In the US it's middle-eastern muslims. In the UK, you can add south asians to that mix. Even here in Australia, 'muslim' doesn't evoke imagery of Indonesians, even though we're right next-door to them and have decent trade links. And before Boko Haram made the news, the general public had no idea that muslims lived in sub-saharan Africa, except maybe around the horn near the Arabian peninsula.

In short, it's an "anglo stereotype of muslims" ban, minus countries with good business links.