The problem of relativistic synchronisation

When I read the contributors to the French and Anglo-Saxon forums, when I read Einstein (three lines of explanation) or Poincaré (one line of explanation), I realize that it is very insufficient.
The theory of relativity is sorely lacking an article on the bases of the theory and the great problem of synchronization, that is to say the relations between space and time.
Einstein does not speak of the causes of the invariance of the speed of light, and he does not even explain that the measurement of the speed of light is in fact only a transversal decoy for a teletransverse observer.
What he does is just think and give a famous postulate, but written in haste, and without explanation. A postulate moreover taken once again from Poincaré.
All this is very insufficient.
It is urgent, I think, to rewrite an article, at least two pages long (and not three lines) on the very foundations of the theory.
The most difficult thing is not to understand things (I have a fairly clear understanding) but to write them in a simple and universal way, and especially by getting rid of this idea of ​​a FUCKING FLAT PLANE OF PRESENT TIME that clutters the thoughts of men from Methuselah to even today's physicists.
R.H.