It's 2021 and still not close to fixed, how do you propose they'd fix film half a century ago or more?
The problems being discussed are more than just the ability of film at the time to capture things , it's the education around it. Shirley cards and books around that time were built to normalize white skin and blonde hair. It wasn't even considered a problem at the time that black skin wasn't reproduced well until furniture and chocolate manufacturers complained that their products weren't well shot.
There's both a technical and a societal element to it.
I suggest watching this video , especially from the 25 minute mark
Centuries of collective effort by engineers and chemists went into these photographic technologies. If photographs of wealthy people in Rochester, NY in the first half of the 20th century had looked terrible, they would have kept tweaking the technology until they fixed it.