Race actually is based on phenotypes. It’s in the definition of race. Race is also based on ethnic/cultural/religious differences, but physical characteristics absolutely are part of what people call race.
Yes, there is no science backing the idea of race or humans being different based on race, but there is science backing the idea that humans distinguish other groups based on physical characteristics. That is the conversation we are having, not whether people actually are different based on where they grew up or what they look like. Just that humans will use looks to distinguish groups of people, along with other differences.
ShakeThatYam