Nobody was able to prove that light speed is the maximun speed possible to achieve, only a theory tells this.
The speeds we can achieve are insignificant compared to the speed of light, how much? 40,000 km/h???, what is 40,000 km/h compared tp 300,000 /second?!
The only things we can accelerate near the speed og light are charged particles, in other words, electrons and protons. The only thing that experience tell us is that an electron becomes more difficult to accelerate as its speed is increased.
How do we accelerate a charged particle? The only way we know to do it is by means of an electromagnetic field and here the stoey gets complicated.
When we accelerate an electron by mean of an electric field the electron moves, as an electron is a charge and a moving charge is a current and a current creates a magnetic field that at its time will create an electric field. To simplify, we accelerate an electron by means of an electric field and so the moving electron will generate an electric field that oppose our accelerating electriv field.
Bigger the speed stronger the opossing field, it will be a moment when the reaction field will cancel our accelerating field, the resultant force on the electron will be zero and the electron will not be able to accelerate further, no matter how strong will be our field or how many miles long is our hadron collider. This moment is when the electron is traveling at the speed of light and this has nothing to do with Einstein's Relativity theory, that is not an electromagnetic theory, ignores electromagnetism and light is a particle and not a wave.
An electron can travel faster than light, but we have no means to do it because it doesn't respond anymore to our electric fields that are the only way that we know to make him move.
As an analogy, a tomate that is not a charged object, doesn't respond to electric fields.
We can put a tomate in a super maximum hyper hadron collider and the tomato will not move.
The conclussion will be that the maximum speed that a tomato can achieve is zero and it has an infinite mass. Nothing can travel faster than a tomato that doesn't move at all.

Stupidity also evolves!