RISC OS has been limping on thanks to the efforts of some extremely hard-working volunteers, but a roadblock is coming. The Pi 5 drops support for 32-bit ARM code, in which RISC OS written, and since enormous chunks of it are written in assembly, there is no trivial way to port.
Even so, it's heartwarming that people continue to put efforts into operating systems that aren't related to Unix or Windows. I'm happy to see people use this, and AmigaOS, and BeOS, and others. Computing shouldn't be a monoculture.
BeOS/Haiku are surprisingly modern considering their age. They made a lot of technology choices at the time that short term were limiting (multi threading everywhere) but long term were very nice. It was just that the short term issues was one of many anchors of them when they needed everything to go their way.
Haiku is the closest of these to being daily runner ready but like a lot of systems, lack of driver support prevents it from that lofty goal. It is pretty much the only reason that Linux has been able to go so far.
Even so, it's heartwarming that people continue to put efforts into operating systems that aren't related to Unix or Windows. I'm happy to see people use this, and AmigaOS, and BeOS, and others. Computing shouldn't be a monoculture.