A consumer cannot dispose of a product correctly if nobody has said what it is made of. That is the whole problem in one sentence, and it sits upstream of every household in the programme.
The producer registry asks for four things: barcode, material composition, packaging type, and recyclability. From those four fields the platform can generate a correct disposal instruction for every unit of that product sold anywhere in the country.
In return, producers get something they have never had: product insights showing how their goods are actually disposed of downstream. Several have already changed packaging on the strength of it.