I'd suggest the distinct difference is one's tolerance to others' opinions arguments, and attitudes insofar one can easily express tolerance of others and be stubborn yet being a tolerant bigot is an oxymoron.
Fanatic or Zealot
The antonyms of bigot could be open-minded, tolerant, accepting, or unbiased.
A bigot is a blinkered, narrow-minded person, usually also very intolerant and unable to see anyone else's point of view. People can be bigoted about things that have nothing to do with race, for example, religion, gender, or sexual orientation.A racist is someone who believes in the superiority of one race over another, or who acts differently (usually negatively) towards a person or a group of people because of their race.All racists are bigots, but by no means are all bigots racist. That is, a racist is a bigot against a particular race or every race except for his/hers.
A synonym for someone who stereotypes could be a "prejudiced person" or a "bigot."
illiberal, bigoted, partial, prejudiced, anti-semitic
Stubborn?
Hardheaded and stubborn can mean the same thing. They are synonyms. Hardheaded can also mean realistic and pragmatic, but usually it means stubborn. If someone is stubborn they could be called hardheaded and vis-versa
The difference is between direct communication (You are stubborn) and indirect communication (This is the second time we are unable to reach an agreement). The first is explicit and straightforward, while the second is more subtle and implies the same message without directly stating it.
I am a Bigot
Julien Bigot is 159 cm.
Marie Bigot died in 1820.
Antoine Bigot was born in 1825.
Eugène Bigot died in 1965.
Eugène Bigot was born in 1888.
Christophe Bigot was born in 1965.
Vincent Bigot was born in 1649.
Vincent Bigot died in 1720.