The putative year in which Linux will be the predominant user desktop operating system

"'The year of Linux on the desktop' is a meme for a specific reason. It'll take longer than a year. The claim is funny because you imagine the whole world switching to Linux, like, overnight. Which is obviously unrealistic. It's a gradual process.
But last year [[2020]], Chromebooks outsold Macs. Chromebooks are Linux. Even if they're not 'Linux Linux,' there isn't much you can do with one that you can't do with most other [operating systems]. Which demonstrates that the barriers to adoption are falling and a major factor is now the need for better marketing."
—[https://news.ycombinator.com/item?id=28958640|Hacker News]

I'd add quite a bit to this. It's more than just the OS itself that is holding Linux back from popular adoption; it's also the applications that people need in order to enable them to work and create. Everything Internet is covered by Linux—OSes–web browsers are cutting-edge, there are many office suites allowing people to write, calculate, organise data and present information. Video and sound editing are mostly covered, and even gaming on Linux is getting better and better almost by the week. I can surf the web, write documents, watch video and listen to music, and [daily driver|I'm settled]. But for many others, the appeal of privacy preservation, control and the open-source philosophy are not enough to drive them into the welcoming arms (well wings of [Tux] the friendly penguin.

Where are the gaps?

One application that has defied emulation and incorporation is [Photoshop]. Photoshop is the one application that defies all attempts to run under GNU/Linux, and yet almost every creator needs a good way of producing, editing and improving photographs and graphics files. There is no Linux port, it doesn't play well with [WINE], the emulation layer that allows many native Windows applications to run in Linux. This means that anyone needing to use Photoshop has to run it under Windows or MacOS, and this is a painful thorn in the side of many open-source aficionados. The [GIMP [by wwwwolf]|image editor program GIMP] will run on almost any machine capable of having a Linux installation, but it falls short in so many ways for professional use. The [Krita] paint program and the unfortunately-named GIMP together can do most of what Photoshop does, but it's still falling short—after all, who wants to take [shampoo and conditioner|two bottles] into the shower when one is what's needed?

In the business world (and even for many regular people), a good office suite is crucial. The two major open-source options are [Libre Office] and [Open Office], each of which offers powerful [word processor], [spreadsheet] and [presentation software], but they fail when it comes to exchanging files with users of [Microsoft Office]; often some formatting is missing, mangled or missing the mark in some way. This is down to an inability to convert to and from the proprietary document formats used by Office. Even the [Open Document Format] used by Libre and Open Office often fails when opened by MS products because despite its being an open-source format, it seems not to have been fully adopted by Microsoft's engineers in their office suite. If only MS would apply it correctly! But that's unlikely as they are not interested in co-operating with the competition.

My 2¢ on the real reason why universal adoption is unlikely

"The man who stands at [a strange threshold],
"Should be cautious before he cross it,
"Glance this way and that:
"Who knows beforehand what foes may sit
"Awaiting him in the hall?"
—[Håvamål proverbs]

I've written a bit about Linux in the past, even touching on the thorny business of [Linux distro|Linux distros] and [desktop environment|desktop environments] and have used nothing but Linux for almost ten years..
There are hundreds of distros, far more than I could begin to name. In short, a distro (short for distribution) consists of the [Linux kernel], a way of interacting with it, and the tools required to use the computer hardware. Most have differing methods of installing and managing programs, differing philosophies on some basic tools (from the way that the bootloader operates to how system processes and daemons are handled). Within the wider Linux community there are still [holy wars] over such things as [systemd], not to mention terminal emulators and commandline interpreters. For the common, non-geek user, these things are baffling.The first hurdle, "how to pick a distro", is tough enough. Add to this the bewildering variety of [desktop environment|desktop environments] available in each distro creates such [choice paralysis] that [inertia] sets in and people stick with what they have (even if sometimes keep grumbling about it anyway).
In an ideal world there would be an easy point of entry and easy ways of customising the system, to reduce complication and get people in the door. But of course then there'd be yet another option to complicate matters, and as ever [there's an xkcd for everything|there's an xkcd] for everything [xkcd] cartoon [https://xkcd.com/927/|covering this very thing]. This illustrates perfectly the major barrier to wide-scale Linux adotpion. Until we solve this, The Year of the Linux Desktop will remain, like [Tibb's EVe], a day that will never come.
Given the current trajectory, it's going to need a [sea change] in the open-source OS community to enable mass adoption. Some speak in hushed tones of [Zorin OS], which is seemingly aimed firmly at users wishing to transition away from [Windows] and [MacOS]. I've looked at this, spoken to some users, and I believe they may have a point. But that's only the first step into adoption. After the OS is on your PC, you will need the applicable tools, and that total integration has to come next.
Where is the next [Richard M Stallman|open-source Messiah]? Who will move and enable a whole developer community to give us the software we need to replace the Microsoft and Adobe offerings? Once that one steps forward perhaps we can talk more hopefully of the Year of the Linux Desktop. But does it really matter? I'm happy just to have an alternative that gives me a choice ☺.
</2¢>

[Jet-Poop] says The main problem with Linux is that it's never going to be accepted by the masses, because the masses want an operating system that just works, without the necessity of learning to code it. Linux can only be a niche system, and that should be enough. 🐉💥🥸 ^†

$ xclip -o | wc -w 821

^† Dragon and explosion added because Jet-Poop asked me to [zhuzh] up his comment. I know, it was a joke, but doing it has cheered me some 🤪/big>

The Year of the Linux Desktop (thing)