Since the original Cyberpunk concepts are now just as retro-futuristic as Steampunk, just like most Steampunk settings put them in the era that first spawned them. I'd like a Cyberpunk game that's set in an alternate 1980s.
Wireless networks are a big one. It's not so much that the behavior of hacking necessarily changes but the consequences are different. In the wired retrotech hacking model the runners need to be physically connected to a phone line or network. Security countermeasures might do things like fry the runner's modem or deck (or brain) with a power surge on the wire. Part of the PC's task was getting a runner to a suitable access point and protecting them while they're running. Being able to netrun wirelessly removes a lot of physical consequences for runners.
Frying your brain was an 80s thing. Modern ICE engages the runner in a debate over whether an godlike future AI would torture identical future duplicates of those who don't contribute to it's development, to the point where the runner calls the corporate police to come put them out of their misery. The old days were kinder.
Then again, I can easily see runners being silly enough to install electronics into their brain to get that FasterBetterSuperVHDSesnaround experience. In which case they're vulnarable to "NOT READING CENTRAL NERVOUS SYSTEM: ABORT RETRY FAIL?" attacks. Or maybe having their sensorium being ransomed. Smart runners would be the ones who are bottled up tight; they are running completely blind to all the omnipresent attractive 3-D virtual overlays of the modern city, with their accompanying cookies and tracers and infoworms and viruses. They have to walk right up to sealed networks and physically plug in, because otherwise they'll be made and ID'd and blocks away from their target a group of smiling fellows will walk up to them "Going somewhere comrad?"