Admin here:
This image shows the hyopthetical scenario of someone buying existing SODIMM sticks and desoldering the DRAM chips and soldering them onto DIMMs. I don't recommend doing this because it'll be cheaper and more reliable to just use a DIMM-to-SODIMM adapter, and the performance would be about the same.

Buying new DDR5 chips and soldering your own RAM probably won't let you save much money either. DDR5 sticks already were one of the PC components with the lowest profit margins, lending to the fact that everybody used them and they are generally not that marketable.
What these will enable, however, is it'll let people like laptop repair places tap into existing stock of DRAM chips currently being sold through electronic parts suppliers. They will charge their own markup for hand-soldering them, which will likely still be lower than buying similarly specced RAM from a reputable manufacturer.

We are in for some dark times.