Obviously it's a minority because the cuisine's he's butchering are by definition minorities.
Food is a massive part of culture and heritage, particularly for immigrants, and it's a source of pride and connection to where you come from.
So when someone like Oliver rolls up, absolutely butchers their national dishes, launches some new hedge-fund backed restaurant chain that puts all the local family run restaurants out of business, and then leaves when that food's not trendy anymore it's makes people angry.
Where I am, we lost a couple of really good, family run Italian restaurants that had been going for 40 years when Jamie's Italian come along, and they don't come back just because Jamie's went bust. Same thing happened with Giggling Squid and Thai. Fortunately the local Carribbean kitchen is still going despite Turtle Bay's pathetic imitation opening.
Hiring a person to say "look, we're not inauthentic, we've got this Jamaican/Thai/Ghanian/Mexican on staff who say it's legit, isn't going to solve the problem or stop people hating the business model.