The average netizen is aware of the fact that the majority of internet traffic comes from mobile devices, when people look at such statistics it might seem mobile is better than desktop, however this only points to the fact that mobile devices are cheaper to acquire and more convenient to use.
Lately I've found myself removing applications from my mobile device in favor of accessing those same platforms from my laptop. The reason is quite simple, the average pc has much more power than the average mobile device as such developers can cram more efficiency and features in it than they can with mobile.
A lot of people might be shocked to know this but your mobile browser doesn't hold a candle to what a your desktop browser can do, software engineers understand first hand how much difference exists between mobile and desktop (having built these things).
Except a platform was made to be accessible specifically for mobile you'll get a better experience on desktop, most websites are built desktop first anyway (by desktop first I mean that these websites were built for desktops before special instructions were written to ensure the website can still function on mobile) and mobile responsiveness doesn't beat a much bigger screen.
You also find that utility applications like office software, programming script editors and the likes work more efficiently and with more features on desktop than they do on mobile. While some agree that it is possible to code on your mobile phone, it is general knowledge that you'd get a lot farther on a desktop device.
This article doesn't aim to get into an unhealthy rivalry of mobile VS desktop, it just seeks to point out the fact that as a budding software engineer you'll need to rely on desktop a lot more than mobile and you'll need to know why quickly in order to appreciate the machine we call desktop.