Why do classical guitars have to use five-line notation?

In fact, the people who read the five-line music may not understand the five-line music and six-line music, but the five-line music of the piano is both the form and the sound, so the piano can read the five-line music very well, but the guitar is free. If you tune it right, it doesn’t matter where it is, most of the people who talk about classics die as a pianist.
Five-line music is specially produced for Piano and is not suitable for guitar. I firmly oppose the use of five-line guitar, whether classical or ballad electric guitar, even though I have no problem looking at the five-line guitar. Many people don’t understand harmony when they read the five-line spectrum. They only play mechanically according to the spectrum. It’s difficult to practice and they forget it quickly. It’s all time. “Lose the five-line spectrum, learn points and sound, you can fly freely,” an appeal from past generations
In fact, harmony, counterpoint and so on are special subjects, which have no direct relationship with the ability to read music. If you want to study acoustics and other disciplines, you must have some advantages in reading the five-line spectrum than only looking at the six-line spectrum (so-called only looking at the six-line spectrum refers to only recognizing the location of the spectrum). It seems that no music theory can be explained by six-line notation, although I do not understand music theory.
If you can still play beautiful music with six-line music, I don’t think anybody will laugh at you because you can’t write five-line music.
Many tunes are composed by five lines; many introductory, hands-on exercises are composed by five lines; at present these tunes have not been turned into six lines or are difficult to find, so if you want to play these tunes, you have to learn five lines, which can be said to be compelling, unless you do not bird these tunes.
Five-line spectrum is not difficult, it can be learned in a few hours, but the process of familiarity needs to be relatively long, in fact, six-line spectrum is the same, to achieve an immediate correspondence with the fingerboard, it also takes a long time to practice.
As far as guitar is concerned, the six-line spectrum has many advantages, but it has to be admitted that many six-line spectrum errors, not the six-line spectrum itself, but the irresponsible producer.