I have a DM250 that I bought a year ago that's been collecting dust because I couldn't get used to the UI/UX. It was imported straight from Japan so I'm pretty sure it's not the US model although I'll have to confirm that.
Customizing / tinkering with it has been difficult because it's a pretty niche product with not a ton of information online (at least on english websites).
Skimming this tutorial it seems like installing OpenBSD is a high-risk / high-reward type of thing. I'll have to look into further to see if it's worth it.
[1]: https://pomera.us/products/pomera-full-suite-typewriter-for-...
[2]: https://kakaku.com/item/K0001457601
The list price appears to be ~USD 380, which is still a hefty saving compared to what they charge for the US model. There are of course software and hardware differences [3], but if it is primarily the hardware you are interested in, I see no reason not to at least consider importing one.
[3]: https://pomera.us/pages/support-help-support-pomera-dm250us-...
Main downsides with the DM250 seems to be that you need a USB-C dongle for audio (they are tiny though) and that you can not hook it up to an external screen for better ergonomics and presentations. Still, small, means compromises are necessary, and I do not think the external screen is a deal break if one would consider the DM250 as a daily commute driver.
LFS/BLFS. Which BSD has that?
I don't disagree with you fully, mind you, but I think this is mostly because many more noobs use Linux, whereas on the BSDs more people with a lot of knowledge use it. But even then I would reason that there are more experts using Linux than OpenBSD, simply due to numbers alone. Not all of them can be bothered to write blogs either. (And sometimes they have reallife hardships suddenly, such as Fefe.)
There is a reason the top 500 supercomputers all run Linux. No BSDs there.
That comes with the system. Here's the manpage: https://man.openbsd.org/release
They can’t have it. The BSDs are a complete system, where the kernel and utilities are built in sync. And building them is quite easy.
Linux complexity may give you flexibility, but most users systems are fairly simple. OpenBSD has a lot of documentation, and if that’s not sufficient, you browse the source code to see what’s happening.
The afterdark screensaver is a real cherry on top.