Jokes aside:
there is no easy answer. If your system des not support pcie gen 4 ssds, its nonsese to get one. you can get one but it wont be faster and it will presumably run hotter than pcie gen 3 nvme.
If it does, however, pcie gen 4 ssds are WAY faster (provided you can cool them properly under sustained load)
Cooling the ssd is critical or your performance and TBW will plummit.
Furthermore, as discussed in How do SSDs fail? - #25 by Fuzeguy
Manufacturers TBW are just a mere wild guess as manufacturers cannot test the actual TBW of their drives (often in the PB zone). It is however agreed on that larger drives have a larger tbw as well (and might offer slightly more speed and/or allow for larger plots)