Yeah it's supposed to be a tribal mask.
The pitch-black face with light, thick, tube-like lips is a cartoonish caricature of an african face.
People associate that with racism because the so-called "blackface" was used in America back in the day to make fun of black people.
But it wasn't the face that made it racist, it was the portrayal of african-americans that made it racist.
The face itself is just a silly exaggeration of reality. That's what caricatures are.
But Japan doesn't associate it with that.
To be honest, I actually think this tube-lip on dark skin design looks actually pretty cool. So it's disappointing that it has been tainted with this racism connotation. Oilman's face for example looks cool. The light lips make a great contrast.
But you can't use that. Even if it's on a creature that isn't even human. >_> Otherwise you'll be labeled racist and people want to lynch you.
Let me tell you a little anecdote:
When I was little my favourite children's story was Jim Knopf und Lukas der Lokomotivführer (in english: Jim Button and Luke the Engine Driver). It's a story about a black kid called Jim and his best friend Luke who go on an adventure with their locomotive.
The illustrations in the book use exactly this design to portray Jim but
nowhere in the book are there ever any reference to racism in any form. No one treats Jim differently, Jim himself is just an ordinary kid who happens to be black.
So when I got older and learned about actual racism towards black people I had no idea what they were thinking.
What's my point here?
It's that this "blackface" itself, without any actual racist connotations is not racist. It's just a caricature.
So people should stop treating it like something made by the KKK.
Jynx is not racist, the squid boss from Wario Land 3 is not racist and this mask is not racist.
Americans only associate it with racism.
It's like the Hitler mustache. It's guilt by association. There's nothing bad about Hitler's mustache. Only that Hitler wore it.
If he had worn a long, twirly moustache then that would've become infamous. But people still make a fuss if a character happens to have a similar mustache to Hitler's. It's stupid.