Yes, mobile-first design has greatly accelerated the decline of usability in interfaces, but that decline also began before mobile-first really became a thing.

All I know is that usability keeps getting worse as time goes on. Where is the floor?

> Where is the floor?

You could try to cram it into an Apple Watch?

That's still good compared to the chat-only interfaces of the future.

And I thought Next-Next-Finish was bad...

mIRC is very powerful, but most '90s, Windows power-users needed some explanation of how to use it, whereas Slack's design language makes it install-and-play for even basic users.

Mobile design isn't just a response to the limitations of its hardware; as technologies become more prevalent, intuitiveness to increasingly inexperienced users has to be prioritised over everything else and this is a major trend that dates right back to the beginning of the computer industry.

Usability is much better today than it was in the past; it's just no longer targeted at us.

I currently ship a web app, which among many things contains an 'excel grid clone'. My earlier team collaborators, who by now have jumped ship to other greener pastures, styled the grid in 'that modern way', so on a huge ultra-HD resolution monitor, you could view maybe 9 columns at a time, if you squeezed them a bit :-/. Soon after the CSS guru was gone, I changed that grid CSS to instead honor the spirit of Excel, and it is now possible to view more than 9 columns of data, and more than 7 rows :-/. I still in vain try to fathom the mindset that would make you turn 'excel' into a bottleship-scrolling-microscope-hell.