How to add a drive to a desktop computer case?

Why don't PC cases have external drive bays anymore? pc case with optical drive slot Standard ATX power supplies, regular height expansion cards, regular height RAMs, hard disk drives this case takes them all Thanks to its dual pcie 4 in pcie 3 slot INPLAY PC Case Gaming Case Computer Case Desktop case Matx case Tempered Glass Side Panel With 2X12CM Fans Slot Wind01Wind05

pcie slot configuration gen1 gen2 gen3 In modern computers, the bays are used for optical drives, the IBM Personal Computer 5150