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Out of curiosity, why don't more of such production lines have dedicated machines that each do one small/simple action and then send it to the next one.Specialising your tools or machines comes at a cost: inflexibility, specifically changeover time between different products. If your machine can only do exactly one thing, the changeover time is "physically replace the machine", which may mean a delay of months.
Changeover time is a massive, hard-to-see drag on everything in a factory. The ideal manufacturing machine station can instantly switch its use between any two consecutive products moving along the line. Physically impossible, but ideal. Fully-programmable robots are much closer to that ideal than single-purpose machines.
That said, the tradeoff depends on the product/process spectrum. Some products are produced in "job shops", meaning an extremely flexible, high-touch environment, turning out very short runs. Others are worker-paced or machine-paced (which is what the Playstation factory would count as), mostly this is used for consumer goods. These still retain some flexibility, as much as sensibly possible.
At the far end are "continuous process" plants. These are very specialised to the product. Bottling plants, chemical plants, oil refineries and so on, where flexibility is not a highly meaningful advantage and the product lends itself to being treated as an undifferentiated flow as opposed to discrete units of product.
I recommend Matching Supply with Demand by Cachon & Terweisch as a first book to read. Then follow with the more in-depth Factory Physics by Hopp & Spearman.