Hello levinceret,
Thank you for your answer; I also had other information, identical or similar; and I consulted a lot of information on Internet... and there...
in short, 2/4, 4/4, 4/8 ... it's always a tango, with maybe a difference between simple tango, hananera, milonga ...
The right hand makes the difference but the left hand always plays the same. And to dance it too, except the Argentine tangos.
Finally, there is the problem of the ease of writing and especially of readability; 4/4 remains more "airy" in reading.
Well, the debate is closed.
And the same problem for the pasos-dobles, in 2/4 and 4/4; better El Relicario and Sombreros and Mantilles are in 3/4!
Musically
La Cumparsita