I‘ve thought of the same thing earlierHopefully enough so that is significantly lighter than the 13" MBP.
An other way to get a true "thin and light" MacBook Air while being cheap is bring back the old 12" MacBook but this time powered by Apple Silicon. It could be priced at $899 or $999 while being significantly lighter than the 13" MBP.
Actually, this is more complicated than we imagined.
If Apple remade the 12 MacBook with A16, 12.9in display, better design, it would not be much different than the 13in Air, it is quite useless because of the tiny display. It would not replace the MacBook Air because M1M2 Air is still fast for media production and several tasks that need performance. The 12 in Macbook is so small that it is nothing more than a Microsoft Office/Youtube notebook. MacOS would not look decent on such a small display, iPads could do the job better.