Scientists prove themselves wrong all the time.

That’s precisely what makes it science.

Science has to be falsifiable.

Regarding the speed of light, the way you speak about it shows you don’t actually know much about the topic.

The speed of light being the speed limit of the universe is an observation and a supposition. Scientists didn’t just decide on it.. Firstly they realized that the speed of light was constant. i.e. it never changes. It took Einstein’s special theory of relativity to show why and how it never changes. The mathematics of relativity also show us that it would take literally infinite energy to accelerate an object to the speed of light. That’s when we first codified light speed not only as constant, but also as the “speed limit” of the universe.

But guess what.. Scientists are constantly coming up with tests and experiments to try and prove Einstein’s relativity wrong. But so far, relativity still remains to be proven correct.

So yes, according to the our best working theory of understanding the universe, we cannot travel faster than light. But scientists acknowledge that the theory is incomplete, and are constantly trying to find the next step in understanding.