¡Hola!
We know there are users who are interested in a single variety of the Spanish language, but we also know there are others who are interested in other varieties as well. Be that as it may, the differences between Spanish dialects cannot be reduced to the use of ustedes and vosotros, as there are many other details which have to do with areas such as pronunciation, vocabulary, and even grammar.
There are six Spanish dialectal regions (México/Centroamérica, Andes, Río La Plata, Chile, Caribe and Iberia/Europa), which imply an enormous variety of Spanish accents and words, as well as grammar rules. Unfortunately, it is not currently feasible for us to include such a range of differences in a single course, at least for now.
This is why we chose Neutral Spanish, which allows the greatest number of Spanish learners/speakers to understand the message without the use of local terminology and certain verb tenses.
From a purely linguistic, non-ideological point of view, Neutral Spanish is just an attempt made by linguists and translators to choose terms that most Spanish speakers will understand, by avoiding the use of vernacular terminology and specific verb tenses. Since we want our users to be able to communicate and be understood by the entire Spanish-speaking population, we offer them the opportunity to learn the neutral type, so they will then be able to adapt what they have learned to their favorite variety of the language.
We will be adding more content in the future, as we understand the importance of offering a more in-depth view on the different varieties of Spanish.
In any case, we have also included the pronouns usted/ustedes in the sample conjugation tables that you can check in our Grammar Hints section, where you will also find some insights into the differences in the use of personal pronouns between European and Latin American dialects.
¡Feliz aprendizaje!
Javier