In my opinion, for production use it's currently best suited for use as a free virtual machine for old software that no longer runs natively on Windows. If enough APIs are covered, it can be an excellent replacement for an XP VM to run some ancient tools.
In theory someone could take modern Firefox, figure out what essential APIs are missing, and contribute a set of fixes to get the latest LTS version of Firefox working again, but that's quite a complicated process.
https://msfn.org/board/topic/182647-my-browser-builds-part-3...
FreeBSD is a great option for a modern stable OS that can run pretty much everything linux can. Desktop system is also easy to install via DarkMate[0] on vanilla FreeBSD or then go to e.g. GhostBSD[1] that has all the bells and whistles from GUI installation onwards.
[0]: https://github.com/broozar/installDesktopFreeBSD/
[1]: https://ghostbsd.org
Why go to alternatives when linux is available?
The question works both ways.
If you compile your own user space software or it's already ported, then yes. But it doesn't have the same driver or virtualization support Linux has. I haven't tried any of the BSDs on a laptop for about 4 years but power management was abysmal then.
Haiku seems to be headed that way, though.
HaikuOS is a hobby project, it doesn’t have the industry relevance to be serious enough for a solid release.
Gnu Hurd’s only benefit is having a micro kernel. Minix, QNX, and possibly other actively developers OS’s have that market. It hasn’t been updated in 6 years and will fade. There’s already Linux anyway.
But majority of indie OS mindset was suddenly captured over past couple of years by SerenityOS. It is a good project in itself, but goes to show 1.0 does not matter for capturing Dev mindshare.
ReactOS on the other hand is very opaque and unfriendly. The website goes without updates for months. There is a sparsely populated forum that is filled with hostility and frustration from the inner circle. The current release ( made not that long ago ) is based off a branch that the main development moved off of years ago. There is a wiki that shows what is appearing in the next release but it has not been updated since June 28. Most of the project discussion happens at chat.reactos.org but I am not sure how you are to know that even exists. To me, it feels like the project attitude towards the community is that they are useless freeloaders. People better than you are busy doing important work that you would not understand. Don’t bother them.
Another aspect of the end-user focus is that SerenityOS has an emphasis on producing working software that is useful. Despite its alpha state they are redesigning dialogue boxes and controls to be easier to use. Animations and subtle GUI effects are celebrated as are small usability features in applications. Despite it being a project goal to build everything from scratch, there is a large ports collection and some of the most notable live streams show the founder porting popular programs and games. While ReactOS cannot even bother to get a browser working, SerenityOS is creating one from scratch.
I have a huge respect for the ReactOS achievement but it is no great mystery why a project like SerenityOS has had more momentum. In my view, the way the ReactOS project is managed has absolutely held it back. I could say the same for projects like GNUstep unfortunately.
Projects like Haiku have not bottled quite the same magic as Serenity but Haiku is very community friendly and it shows. Haiku is also pragmatic and, while the goal is to mimic BeOS and to offer an alternative app platform they have built compatibility layers in order to port over apps. They even run WINE. Haiku also has a browser ( not totally from scratch ) and there is already a port to RISC-V. Despite not being at 1.0 yet, there has been a lot of emphasis on creating a working end-user experience.