Why didn't the time patrol ignore Daxiong's creation of the cat and dog kingdom 300 million years ago and rewrite history crazily?

Personally, I think that perhaps the fact that Daxiong created the kingdom of cats and dogs 300 million years ago did not rewrite history, and it was doomed to happen in history, so the time patrol ignored it.

1, Doraemon is a robot in the 22nd century, but that doesn't mean it will know everything that happened in history-it's not a historian robot, let alone a defective robot.

2. It is not necessarily easier to intercept meteorites than to emigrate to outer space. Whether intercepting meteorites can be successful is still unknown. What if it fails? So the president of the cat and dog kingdom should take insurance measures.

3. All kinds of facilities in the cat and dog kingdom should be made according to the engineering principle, but wouldn't it be better to make all kinds of facilities into the shape of cats and dogs on the basis of the engineering principle?

400-300 million years ago, the position of the constant star was not necessarily different from now; To take a step back, even if the position of Hengxing was different 300 million years ago, how can you be sure that their target dogs did not exist when the cat and dog kingdom immigrated? Maybe it exists, but it's not what we call Canis major now.

5. It should be discovered. Maybe people in the 22 nd century have records, so no one is surprised.

Don't forget that anything is possible in the future.