The Reddit thing is also mixed with the fact that Reddit's mobile web interface is complete shit. You can't even collapse threads (or it's so hidden as ot be useless), which is something the desktop web interface does. It might not be the best example of why mobile users want an app, as it's functionally worse using their mobile web version, probably on purpose to force you to their app so they can monetize you... and now we understand why they did what they did and why people didn't want to use their official app, as the way they monetize you is to inconvenience you with more ads.
I wonder if it's to do with desktop usage more linked to typing compared to mobile usage pattern framed around clicks /taps...
(I'd rather use the web interface on mobile and desktop, so I'm not sure the original criticism applies to me, either.)
On mobile, it's a different story, the screen real estate is small, and users can't operate both/one hand(s) comfortably like on desktop. Therefore, if you don't design the app smart enough and make users not comfortable, you're screwed up.
I use an email client because I don't want to deploy PGP keys to the server -- then there's no point.
It's interesting though: on mobile, everyone wants a client application. On desktop, people wonder why bother with client software when we have a browser. "Reddit for Desktop"? Hah, doesn't even exist! But "Reddit is Fun" for Android? People died on that hill.