Design is the art of signal-to-noise ratio, or in simpler terms, balance and harmony. If you over-use any modality, lines, text, color, nesting, you increase the noise level. If you underutilize a modality (for instance your whole UI is monochrome), you reduce your signal bandwidth.
Every trend gets mindless followers, who throw the baby out with the bath water without even realizing it. But trends also bring a grain of gold to the table.
For instance, monotone icons allow many more elements in the same screen real estate than text, and by not using color you can have a larger color budget for other elements, which you can use elsewhere to convey progress, status, or anything else important.
A good use of monotone icons are text formatting (bold, justify, etc) and display options (column view, tree view, etc), or toolbars (like in photoshop or 3D tools). Many apps from the 2010 era overused colored icons, and I’m glad those went away. Some FOSS apps still suffer from that.
Bingo, and it also impresses the upper level management at customer companies - i.e. the ones who make the decision to buy the software, not having to use it themselves
But starting around 2008-2009 I noticed a trend, and it continues to this day- the power user oriented layouts started being replaced with more 'friendly', larger icon, children's game looking UI. Intuitive graphical icons were replaced with stylish, monotone shit that looks like a graphic design student's dream, but conveyed less instant information.
I blame some of this shift on the move in Office to the Ribbon system and developers trying to imitate that, but some software I've seen takes that and does it much worse.
I want all my functions laid out and accessible. Like this blog post mentions, sometimes I don't know what I am wanting to do until I see it. I want to be able to explore the entire space before I know what it all does, maybe.
Using natural language can be very powerful if it augments these systems, but for many tools it isn't a replacement. Often I think new software is designed around looking impressive and fast to upper level management at the expense of the usability of the power users who ultimately are the users that get things done.