Gadgets

Not OP and unsure of which specific SSD they are referring to but it could be that PCIE is both a data transfer standard and a physical connection on your computer. Saying "PCIE 5 PCIE SSD" would specify that it both uses PCIE 5 data transmission protocols as well as the physical PCIE slot.

Simply saying "PCIE 5 SSD" could leave some ambiguity as to whether the SSD is installed in a PCIE slot or an M.2 slot, with the latter being more common but also being less powerful (although still more than enough for the average user). Simply saying "PCIE SSD" is even less clear as it could be any PCIE specification in either a PCIE or M.2 slot. Not relevant for this specific question, but saying just "M.2 SSD" would be very unclear as well as you know the physical slot it will go in, but you now open the door for it to use the SATA transmission standard which will bottleneck modern SSDs.