Explain. The wiki you linked to specifically states that it is descended from Tibetan script, which is in turn descended from Proto-Sinaitic script.

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austin-cheney an hour ago | parent [-]

The article said nothing like that. It was an original script invented by a Tibetan monk at the paid directions of Kublai Khan.

> Descending from Tibetan script, it is part of the Brahmic family of scripts, which includes Devanagari and scripts used throughout Southeast Asia and Central Asia.[5] It is unique among Brahmic scripts in that it is written from top to bottom,[5] as how classical Chinese used to be written, and as the Mongolian alphabet or later Manchu alphabet is still written.

https://en.wikipedia.org/wiki/%CA%BCPhags-pa_script

> The origin of the script is still much debated, with most scholars stating that Brahmi was derived from or at least influenced by one or more contemporary Semitic scripts. Some scholars favour the idea of an indigenous origin,[19] or connection to the much older and as yet undeciphered Indus script[20][21] but the evidence is insufficient at best.

https://en.wikipedia.org/wiki/Brahmi_script

So maybe, but probably not and this particular language though it has roots elsewhere of debated origin was an original spontaneous creation.

	▲	cwnyth an hour ago \| parent [-]
		"but probably not": Actually, probably so. The scholars who favor the indigenous explanation are a small minority outside of India. It's possible it was independent, but very, very doubtful, and none can explain the enormous gap in time between the Indus script and later Brahmic scripts.