It appears to be somewhat hereditary. My daughter and I have it but my son does not. When I look at color blue and purple, I see a smudge so when there letters

It appears to be somewhat hereditary. My daughter and I have it but my son does not. When I look at color blue and purple, I see a smudge so when there letters such as store names far away, I absolutely can’t read it. It appears like all the letters are smudged. I recently bought a InstaPot cooker which has blue color led lights. The previous mode had red. I can’t read it from far. I have to get close to read the blue led lights. Edit: edited for clarity.