The argument raises a real question about the reliability of one transmission route, but it does not destroy the Quran's transmission. It treats a qira'ah chain as though it were a solitary hadith chain, whereas the Quran was preserved through written copies, continuous public recitation, and numerous independent routes.
What the objection gets right
The strongest form of the objection is serious: Hafs ibn Sulayman is heavily criticized by hadith scholars, and reports describe him as unreliable in hadith transmission. Asim ibn Abi al-Najud is also reported to have had imperfect memory. Ibn Mujahid records a reading attributed to Hafs on Quran 30:54 and treats it as an error. If the Hafs-'Asim route were the only evidence for the Quran, applying ordinary hadith criticism would make that argument difficult to sustain.
That criticism also exposes a genuine mistake sometimes made in popular presentations: Hafs is not simply "sound" in every field because his name is attached to the most widespread printed Quran. His reputation in hadith and his authority in recitation must be discussed separately.
Why hadith grading is not a verdict on the Quran
Hadith criticism asks whether a particular report was reliably conveyed by each individual narrator. Quranic recitation was not established by one isolated report from Hafs to Asim. Hafs transmitted one recognized reading from Asim, but that reading was also supported by the written consonantal text, teaching networks, and the recitation of wider communities.
A narrator may be weak in hadith while being a specialist whose recitation was accurately known and transmitted. This distinction is not an ad hoc escape. Classical scholars routinely distinguished a person's competence in different fields. A critic's judgment that Hafs was unreliable in hadith does not automatically mean that every sound he learned and taught in recitation was false, especially when the same reading was publicly taught and accepted through other routes.
Indeed, We have sent down the Reminder, and indeed We will preserve it.
Quran 15:9
What Ibn Mujahid's report actually establishes
The report in Kitab al-Sab'a, including the discussion connected with Quran 30:54, shows that early scholars did scrutinize and sometimes reject particular readings attributed to transmitters. That is evidence of criticism, not evidence that the entire Quran depended on an unquestioned chain.
Nor did Ibn Mujahid invent the seven readings as seven private alternatives. He selected well-known reciters whose readings met the accepted standards of the period. Later scholars formulated those standards more explicitly: the reading had to accord with Arabic usage, fit the early written consonantal text, and possess an established transmission. A weak individual route could therefore be rejected without rejecting every route to the same recitation.
What this argument does and does not prove
It does prove that "Hafs is reliable in hadith, therefore Hafs alone proves the Quran" is a bad argument. It also warrants caution when claims about Hafs's hadith status are presented without qualification.
It does not prove that the Quran is lost, nor that the Hafs reading is merely a late invention. At most, it challenges one oversimplified account of how that reading was transmitted. The Quran's preservation rests on converging oral and written transmission, not on the personal trustworthiness of a single narrator.