We recently published a paper at the 22nd ACM Conference on Computer-Supported Cooperative Work and Social Computing (CSCW) exploring the benefits of deliberately slowing down algorithms for certain tasks.
“Faster is better” seems like a straightforward rule of thumb for designing algorithms and user experiences, and when algorithmic systems were being designed for single-user productivity applications, this rule was probably all that needed to be said about time in design.
However, modern algorithms are very different from the first word processors. In particular, algorithms are now used to make decisions of consequence like who will be released on bail and who will receive preventative healthcare. When a user uses an algorithm to augment a real-world decision which effects others, is it really optimal for them to get the quickest answer and accept the suggestion of the algorithm with no deliberation or consideration of nuance? Probably not.
We conducted experiments where we used an algorithm to augment human decision making on a contrived task, and we found that a slow algorithm can help users be more reflective about the task at hand and be more thoughtful when interpreting algorithmic outputs. To see more about this, take a look at the paper linked above or this Medium post by my colleague.
An additional issue related to time in UX which our work did not address is determining what role the rapid tempo of online services might contribute to some of their unwanted effects. My hypothesis is that fake news, polarization, and the addictiveness of apps are all intimately related to the tempo of interaction in online social media. The advertising business model needs interfaces to be fast, so that loading times are not a limiting factor in the number of page views per minute a user generates.
I think tools that slow down existing social media or social media specifically designed with a slower tempo of interaction  would be more tranquil spaces where our deliberative, rather than our impulsive, selves would show up. However, this would require social media products with fundamentally different business incentives than our current ones, monetized by advertising.
 I’m not simply implying that we have Facebook but with slow page load times, even though deliberately slowing down Facebook probably does make it less addictive and may prove to be more effective at curtailing addictive usage than simply using a tool that blocks the site for specified time periods. Instead, I’m thinking of things like a comment system that delays the broadcast of comments to other users by a minute or more. It would be more difficult to have a heated argument on Twitter if there was a cooldown period in the propagation of what you’ve just posted.