I'm not even a Linux "enthusiast". I simply find Windows to be a terrible product and Linux to be a better product. I simply use the least terrible option.
Unfortunately many people rely on proprietary software packages that don't run on Linux, such as Microsoft Office, the Adobe Creative Suite, and other desktop software tools that serve various niches like CAD, music, video production, desktop publishing, etc. There are often FOSS alternatives that run on Linux, but sometimes these alternatives have shortcomings that hinder adoption, such as lacking necessary features, having imperfect file format compatibility with proprietary file formats, having a less intuitive UI, etc.
With that said, the desktop Linux ecosystem has come a long way over the past 20 years that I've been following it, and I think desktop Linux serves the needs of people who are not reliant on the Windows and Mac ecosystems.
Even if the alternatives were just as good or better, their workflow is likely entirely different. Different keystrokes, different ways of doing everything, slightly different quirks than the "brand name" software.
I like some of the Linux alternatives more than the "brand name" software, but I don't work in media or document creation. If I had all the keystrokes for Adobe Premiere memorized, it would be a pretty tough sell for me to drop that to move to something like Lightworks or something.
The thing is that they're just tools. Having some keystrokes memorized does not mean you can't learn new keystrokes or, in some cases, you can't change them.
When I worked at uni I saw people rescinding when applying for a web design job because the computer they gave to them didn't had Photoshop installed - not that it was required to do anything super special, they just needed to crop images and export them to a given size. People, specially in the media sector, are incredibly dependent on "brand name" software.
I don't disagree, people can learn new keystrokes and workflows, but it just makes it a tougher sell.
Imagine that you've been using Windows for twenty years. You have been doing paid professional work with Adobe Premiere for twenty years. You have a workflow with the two that has worked for about twenty years. Linux might be better, but it's probably not that much better than the setup you have right now, and the applications you have built your business on don't exist on that platform, and there would be a pretty steep learning curve to pick up the new stuff.
I can't speak for anyone else, but I probably wouldn't move to Linux at that point.
Now, if I were already using the Windows version of Lightworks or Resolve, that might be different; a lot of my knowledge would transfer over, and that might be enough for me to change over.
I've been using Linux for a good 25 years. In that time, I've gone from having to tinker endlessly to get things working in a basic manner on a desktop machine, to running on a laptop with essentially no tinkering, and fewer issues cropping up than most of my Windows- and macOS-using friends complain about.
Sure, if you require a piece of software that can't run on Linux, then you're stuck wherever you are. Otherwise? ::shrug::
As former Linux enthusiast, I am alright with it, I rather game, watch hardware accelerated videos, got access to the tools I need, and I need to reach out for GNU/Linux, can always start a VM.
I mean, unless you work in software or extremely high-budget movies, Linux is a pretty tough sell.
A lot of the "mainstream" apps simply do not exist on Linux. LibreOffice isn't so bad, but most people simply want Microsoft Office. Lightworks is decent software, but most people want Adobe Premiere. Gimp is alright but most people want Photoshop, etc.
This isn't to say that Linux software "worse", I actually like Lightworks more than Premiere, and there are some applications that are competitive with the "brand name" applications like Krita, but "having good software available" is only half the battle. People get used to certain workflows, and if Linux doesn't support that workflow most people aren't going to think it's worth it to switch over.
I do work in software, and I run NixOS, and I like it a lot, since programming tools on Linux are generally very good (especially if you work in server-land like I do). I'm just saying that I don't really blame people who don't want to switch over.
LibreOffice is pretty bad. It doesn't tend to hold up past very basic use, and that use case has long since been taken by Google Docs. For serious work - e.g. legal services word processing, or many accounting workflows - LibreOffice doesn't hold a candle to Excel and Word.
The problem with desktop Linux software is that it generally doesn't have the demands put on it that would push it to develop competitively, so it tends to get stuck spinning in circles for decades. LibreOffice Writer isn't really a competitor to MS Word - it's more of a bloated Wordpad. Ditto The Gimp, etc. It's just not there.
Well at least Google Docs works just fine on Linux, I use it all the time, so I don't think that alone would be a deterrent to switch to Linux.
I don't work in law or accounting, and I can only speak to my own experiences, but I have generally thought that LibreOffice Writer is fine. Even back when it was OpenOffice, I edited and formatted a weekly newsletter in high school with it, and it never really bothered me. I admittedly don't use it a lot now, I'm one of those irritating LaTeX people. I've heard that OnlyOffice is better, but I haven't used it yet.
I definitely agree that LibreOffice Calc is considerably worse than Excel though. It works ok most of the time, but even the free online version of Excel is generally better.
I think that Krita is pretty competitive though. I don't work in art but I've talked to people who do and they've said Krita is pretty ok, and at least one person uses it for paid work. There's also Blender, which is (I think) being used for "real" movies now?
Heck, that's going to go down poorly with those who will correctly point out that not only are there a gazillion Linux desktop environments which equates to a lot more than 3 "operating system" choices ("Linux" is just the kernel and a set of included/bundled/related technologies) but that there are also other systems you can daily drive like FreeBSD that aren't even Linux.