No, lots of algorithms and data structures use more space to provide more speed. It's not simple laziness.

I don’t think that’s what Slack is doing here though :)

I’m totally with you for things that are actually doing serious numeric/algorithmic work. Matrix inversion runs a helluva lot faster when the whole matrix fits in RAM. And there are undoubtedly lots of places where you can use different algorithms for the same problem that can trade off memory usage and computational complexity.

It does happen obviously: https://en.wikipedia.org/wiki/Space%E2%80%93time_tradeoff

But yes, running another browser + javascript interpreter on a machine that already has a browser + javascript interpreter running isn't what that article is talking about.

Constraint solvers comes to mind. It's pretty much the most memory hungry application I can think of, though some of the VLSA EDA tools need triple digit GBs of memory to do anything.

You can also increase memory usage for faster software, as is the case with memoization and lookup tables.