have you heard about missing fossils?
You have no idea what you are talking about.
Let's say there is an underground crypt that has been completely sealed since the year 1920. Is it possible to enter that crypt and find inside it a car that has power steering, air conditioning and reversing cameras? Of course not. You can't just say, "Well, maybe they developed power steering, air con and reversing cameras a lot earlier than we thought."
Let's look at why.
Let's assume that they DID invent those things back in 1920, but no record of them survived. Power steering was then invented again in the early 1950s. But then why would the power steering on the crypt car use the same principles as the power steering invented later instead of using a different technique? Why would the crypt car's power steering have all the signs of having developed from the 1950s power steering?
And what about air conditioning? Sure, air con existed in 1920, but it wasn't in cars until 1933. So why is the air con in the car a small miniaturized version and not the larger versions found in the air conditioners of 1920?
And what about the reversing camera? Why does it use the same sort of screen that is found in modern screens instead of a different pattern of coloured pixels? Why does it use technology that is identical to that found decades later instead of having numerous small differences that would not affect how it works but would clearly indicate a different source?
Of course, we would expect that even if somehow someone back in 1920 DID figure out a way to have power steering, and air conditioning and reversing cameras, they would have done so in ways quite different to the ways we do them today.
So if we DID find such a car, we could possibly explain it if it did things differently, but if it did things the same, then we have a much more difficult question to answer. Because we are no longer asking, "How did they have a reversing camera in the 1920s," we are asking, "How did they have a reversing camera in the 1920s that is identical to the ones we have in 2018?"