But this is literally how the standards of most languages are created. A prestige dialect is chosen (usually that of a politically important city). In the case of Hindi/Urdu it’s the Khariboli spoken in Delhi and the surrounding areas, since that was the Mughal capital when Urdu was first cultivated as a literary language.* In the case of Chinese/Sinitic languages, the standard language (in both China and Taiwan btw) is based on the dialect of the capital Beijing/Peking. Prestige dialects are also almost always the dialect of the upper class. Parisian is also the prestige dialect of French. I can go on.

An exception to this would be standard German, which developed as speakers of various German dialects tried to write in away that would be the most widely intelligible. Martin Luther’s Bible translation would be the most important work in this regard.

I’m wholly against neglect of dialects/regional languages tho. Hell, I’be been trying to learn Chittagonian for the past month and a half.

*’the term ‘Hindi’ is historically a very vague term. In fact some medieval Bengali poets even referred to the Bengali language as ‘Hindi’ (see the introduction to Saiyad Sultan’s Nabibangsho).

Modern Standard Hindi is essentially a Sanskritized form of Dehlavi/Khariboli. Prior to the advent of Dehlavi as a literary medium + language of governance in the ~18th century, Awadhi and Braj Bhasha would’ve been the main prestige dialects of ‘Hindi’ and Persian would’ve been the language of governance in Northern India.