That was mostly just my cynical take.

Around 2007-08 I read in a(physical) Brazilian web design magazine that you can have two types of design: - for short, ephemeral experience, your design should be striking - the user will just look at the thing once anyway, so you should capture the attention in spite of how ease of navigation. Eg. a website for a rock band tour. - for experiences that will need to be repeated lots of times (eg. using a corporate system, reading the news), you want the design to be boring and predictable.

I think that minimalism has been used to push interfaces that reduce information density - regardless of how the density would be useful in that context!

After the original Material Design video https://www.youtube.com/watch?v=rrT6v5sOwJg the writing was on the wall: if you want to build a google-grade portfolio, create designs that resemble this. After some time users got used to that kind of look and now sites with high density of information look alien.