Some country out there would not agree to use the language. Even if a perfect language was created, it would be hard for the rest if the languages to die out. There is also a lot of culture in languages that would be wasted through getting a perfect language for the entire world to use.
The purpose of language is communication. A perfect language, therefore, would communicate all details and nuances we want to express with absolute clarity. The amount of detail that would require is too massive to be efficiently conveyed by any human method of communication. If our communication is inefficient, and thus lacks the capability to convey information in a timely matter, it is also imperfect. So at minimum, in our current state, I do not believe we can make a perfect language.
Perfection is absolute and since the "perfect language" IS (A language perfect to expression and perception) -God creates perfection. Any vain, arrogant or wicked attempt to duplicate that which is, is in itself pointless. Still not convinced - recall the consequences to the last endeavor to which "perfect language" was essential, imagine the consequences of a second attempt - not a good look.
Throughout the world language is as diverse in how it is spoken as how it is used. Some languages are descriptive, while others are fact literal. There is no one system or one technique that will allow for a perfect language. How we feel about our world and its inhabitants may be universal but how we describe them and state them to each other varies too greatly.
I do not think it would be possible. People today fight over everything for power. As such people would fight for their language to be crowned the perfect language. Also I think you will always have people that are cut off from the main stream of society and as such will have their own language.
What is considered prefect is subjective. If you ask 10 people how good something is, you will get a variety of answers. Due to this, you cannot create a perfect language. There are many things that make up a language and all languages have different elements that make them unique. Even if someone attempted to make a perfect language it would probably be dispelled by someone because its not as similar to a specific language as they want it to be.