what predictions of the futuretimeline.net come true???
As Matthew said, it depends on the time scale: generally, short term predictions are more likely to pan out as described, and long term predictions can't be as precise.
It also depends on the category of prediction. The ones that don't depend on human trends are generally very regular and almost certain to come true, regardless of time scale. For example, The cicadas will almost certainly re-emerge in 2021. The astronomical predictions, also, will happen as predicted regardless of human intervention.
The more human-relevant predictions can also be ordered by likeliness in terms of category. More or less in order from most likely to least likely, these can be broadly listed as:
- Infrastructure: These predictions come from projects that are already planned or under construction, and therefore are very likely to come true as predicted, though possibly a few years behind schedule. For example, the ELT will happen, if not by 2022 then definitely before 2030.
- Short-term Tech: Moore's law has been very predictable in the past and is likely to continue to drive tech breakthroughs at a predictable pace, and most of the (early) tech predictions in the timeline are based on this trend and are therefore likely to come true. For example, computers are likely to break the exaflop barrier in 2019.
- Natural: Climate change is only accelerating. The only thing uncertain about almost all of the climate predictions in the timeline is that they may happen sooner than predicted. However, because of the complexity of the global system, precision is difficult. That's why I put climate predictions behind the more precise "infrastructure" and "short-term tech" categories.
- Long-term Tech: These predictions are difficult to make accurately and very difficult to make precisely, usually because some intervening cultural revolution (or other tech innovation) takes place that renders the predicted tech breakthrough irrelevant. For example, we won't need to build a trans-atlantic tunnel if some unforeseen quantum mechanical breakthrough enables human teleportation before then.
- Social: Predictions about how society will take shape in the future are almost impossible to make with any precision, and as a result most of these predictions are very broad-brushed (i.e. Gen-Xers in politics). They are designed to give you a general picture rather than hit a target, so to speak. Also, society as a whole is so complex that any prediction about its future always fails to include several relevant factors. Therefore, they're usually off the mark or wholly irrelevant. And even if they are on the mark, it's still difficult to say whether or not they have "come true."
- Geopolitical: These ones are almost complete shots in the dark, and are likely not to come true at all, but they make for great thought experiments and often provoke the most engaging discussions about the future. Arguments about the future of the South China Sea are always more heated than those about Moore's Law.
It's important to recognize the difference between accuracy and precision, both qualitatively and quantitatively, in terms of time-scale. Also to take into account the fact that any one factor is always affected by too many others to account for, when you're making predictions about the future of our world. In general, the one thing that is certain about the future is that it won't be what you expected!