Well unless they want to target PowerPC and make interested parties buy a Raptor Talos workstation what else is open enough for you? (Actually I would support this) Are there RISCV systems that are blobless?

It also documented far better than any other easily accessible hardware. I’d pick the Pi over any other real hardware target.

I think the replies to this post may be missing the point? AIUI The raspi CPU drivers being closed makes it actually pretty hard to write an open driver for it. So you would need raspberry pi or their CPU supplier to write the driver for you, which they wouldn't do for a small OS. It took multiple years to support raspi 4 in mainline Linux and AFAIK raspi 5 still does not have a fully functioning mainline driver. That's why Raspberry Pi OS exists. You would pick a CPU that has open drivers because it would be easier to write your own for a different operating system.

Sure, that's one of the reasons I don't like them. But AFAIK that's not an impediment to running a custom OS, so I think for a lot of projects the tradeoff is good.

And yet there is a wide variety of operating systems available for the RPi, so it doesn't seem to be too much of a hurdle in practice.