Most applications would be distributed as bytecode (e.g. compiled Java or similar) and not as native code, commodifying hardware. You could swap your stuff over

Most applications would be distributed as bytecode (e.g. compiled Java or similar) and not as native code, commodifying hardware. You could swap your stuff over to a totally different CPU architecture and barely notice. The Internet would be a lot less centralized than it has become with a lot more peer-to-peer traffic. The Internet would be very disruptive to political systems and large corporations, promoting a lot more small scale DIY and anarchistic type stuff. (Standard issue 90s techno-libertarianism... we did not understand network effects.) I thought the Internet would decentralize us physically too, making it possible to do the same work from some 'holler in West Virginia as the middle of Manhattan. (I still don't count this one out. COVID pushed us a little further in this direction. This is more a cultural thing than a technical thing, and culture changes slowly.) C and C++ would be dead. Nobody would write in memory-unsafe languages anymore and garbage collection would be ubiquitous. We'd probably have type systems that caught a lot of bugs too. Rust is finally delivering on the latter, so this may eventually come to pass. CPU frequencies would continue increasing, or would at least level off at a higher frequency than they have. I would have guessed 10ghz or so since beyond that the speed of light vs the size of the die becomes an issue. AI would remain very far off. I did not imagine self-driving cars until ~2050 or so. The 90s was still the "AI winter." Apple would be dead by now. X86 would be dead by now. I never would have imagined it would have been possible to get this kind of performance out of that hairball of an instruction set. Spinning disk would be dead. (It is on PCs and mobile devices, but I mean everywhere.) I didn't predict mobile at all. I would have said such devices are too small to have good UIs. How would you use something with a tiny screen like that for anything but maybe texting? I thought we'd all have at least a gigabit (full duplex) at home by now. I was really pessimistic on space, at least in the near-mid term future. I didn't expect to see humans still in space by 2010-2020, let alone something like SpaceX. I was really pessimistic on energy. By now I would have predicted we'd be well into a global depression brought on by fossil fuel exhaustion. We'd be deploying nuclear fission as fast as possible to keep the grid up, but cars and airplanes would become extremely expensive to operate (thinking ~$20/gal gas). We would have reduced mobility but we'd all be connected. I wasn't concerned about climate change because of course we would run out of cheap fossil fuels before that would become a really big issue. ... can probably think of more.