We have that assumption because we’ve worked first hand with managers, developers and designers that don’t care about load times and “snappiness”.
We know from experience, a lot of work gets signed off as soon as they can put a tick in the box to say it’s done and not when it’s actually done well! ;)
Exactly this. Seeing from the inside how products are being built, I strongly doubt that it is ever proven that users want the bulky, shiny, slow stuff.
> but given that the glossy products constantly beat out the minimalist ones
Another theory would be that the glossy products have a much better marketing than the minimalist ones. Nowadays, people just don't see you if you don't have a heavy marketing. IMO it has nothing to do with the quality of the product.
> What if the people who care about load times in apps like Slack are a tiny minority
Haven't you ever heard of somebody (not tech-savvy) buying a new smartphone because their current one is "too slow"? I have. It just feel like those people accepted that "the phone is too old, so it is now slow" (just like they have been taught to accept that most software is buggy). Where I don't. The phone is slow because the programs it runs are (unnecessarily, IMO) bulky. And most software is full of bugs, which makes it pretty bad.
We know from experience, a lot of work gets signed off as soon as they can put a tick in the box to say it’s done and not when it’s actually done well! ;)