So this just happened: https://arstechnica.com/gadgets/2019/09 ... each-cell/
PLC NAND (Penta Layer Cell) NAND memory which will now likely enable a single NAND chip of +1Tb size. Likely will be slow, but with a decent sized SLC cache, they could soon be producing +8Tb consumer SSDs with only a few chips on them.
This might be the last generation of HDDs being manufactured right now. It can't be long before comparable SSDs are less per Gb to manufacture.