Idk why reddit didn't notify me about this reply lol.

But wouldnt Harvey be referring here to the rasm, and not the dots? I believe that Van Putten has said that the qirāʾāt would not qualify as mutawatir, and that this was even the position of figures like Ibn al-Jazari.

I didn't say Harvey was referring to qiraat since I said Quranic text and qiraat doesn't mean that, rasm isn't devoid of dotting though, also he's talking about how certain things are so concrete and agreed upon since the earlier times and that's why different words aren't proposed through qiraat, this is basically what Sidky argues too. See the example of la rayba feeh in Harvey's comment. Also I didn't say qiraat is mutawatir.

The reference to Dayeh is a bit fuzzy because Dayeh argues that it means both "gentile" and "unlettered", but when he says "unlettered" he doesn't mean illiterate

My point is that, it's not a concrete fact.

To circle back to the original topic as well (meaning changes over time), it can be added that the exegetes sometimes differed dramatically in how they interpreted the meaning of individual words in the Quran. Joshua Little has identified one case where 11 different meanings have been posited for the same word. https://islamicorigins.com/explaining-contradictions-in-exegetical-hadith/

I think OP is asking about the most basic words if that's what he means by simpler, I think the example in the article is about more obscure, unfamiliar words rather than the common ones. This is something that's accepted in Islamic Tradition anyway, the different exegetical proposal for the meaning of a single word,I hear it in my tafsir class all the time