If you're picking up a PS5 in the next few days (or you're lucky enough to have already got one), chances are you'll want to play some of your old games on your new hardware. If you're working out how to transfer PS4 games to PS5 en masse, you'll definitely want to consider using a LAN cable to get you playing as quickly as possible.
IGN UK's Joe Skrebels says that when they went to transfer "several hundred gigabytes" of games, their initial approach was to use the console's wi-fi transfer process. In total, however, that process would have taken more than a day, topping out at 27 hours. When Skrebels decided instead to use a LAN cable to transfer their games, that figure dropped to just three hours. For those of you doing the maths at home, that just a little over 10% of the time it would have taken over wi-fi, and for those with less reliable internet is probably the difference between enjoying your PS5 during launch week and having to wait until several days after release.
This isn't to say that you shouldn't use wi-fi transfer under any circumstances. If you're only moving a few smaller games around and have a reliable connection, you probably won't be wasting an entire day moving things around. As a general rule, however, it's probably worth using a wired connection in almost every situation, particularly if you were already storing some of your PS4 games on an external hard drive.
If you're still trying to grab a new console, our PS5 price guide is a good place to start.