That doesn't quite work as an analogy. Reducing speed limits leaves the peak throughput of the road the same: a car arrives every 2 seconds. The only thing it changes is the latency, or the amount of time an individual vehicle needs to travel a given distance.

The purpose is to reduce the chance of the server room flooding (gradually or catastrophically) by some fraction.

As a side benefit, it also reduces the chance of a server catching fire by about half.

To clarify, I was just trying to address the question of whether the magnitude is large, not the question of how to weigh the various trade-offs.

OTOH you can see it as a litmus test (or "foot in the door") for whether people would be willing to make larger sacrifices. Every time there's a discussion of something with a bigger impact, people shut it down because they don't like the personal sacrifice required of them, even when we're talking about their elephant contributions. Yet when you try to start small people still object because the impact is too small on its own and they purportedly want larger changes. I see it unfold right here on HN on almost a weekly basis now. I don't know how to have hope for this planet but it's pretty depressing to watch.

There are far more effective "low hanging fruit" to tackle than lowering the speed limit when it comes to reducing emissions.

- Transporting goods by rail instead of truck or plane. And while we're at it, cargo ships are huge polluters because they can save money when using low grade dirty fuel. Disallowing that practice would have a big effect, but that would require the global community to act (good luck with that).

- Increasing the use of public transport and other ways to lower the need to even drive a car, like (partial) work-from-home schemes, and political incentives driving their adoption.

- Increasing the efficiency of roads, first and foremost by getting smarter traffic flow control that reduces congestion (nothing in transport is more wasteful then a car just idling in a traffic jam). But even the quality of the street and type of pavement you use in roads can have a rather significant effect on fuel efficiency (regardless of whether the fuel is stored in a gas tank or a battery).

Reductions of emissions is one important piece of becoming carbon neutral, but not the only piece. Renewable energy sources and other technologies that will take carbon out of the atmosphere again play another important role in the complex solution that is needed. And e.g. with renewable sources Germany might not look too bad internationally, but we're greatly lacking behind our own goals, and mostly for political reasons.