StarFive catalog parts use slightly tweaked SiFive cores. So if you were going to license a SiFive core for an embedded design, you may want to have something that uses the catalog part to verify your code will work.

I mean, emulating your core for development is a good approach in general, but at some point you may want to run your code on actual silicon.

So sure, an Intel i9 or ARM Mac is probably going to be faster than a 4 core U74 SoC, but if you're using a RISC-V core for some embedded application, having a RISC-V system to test with is probably a good idea.

And it's cool you can get a RISC-V SBC for a couple hundred bux. It wasn't too long ago that you paid $2k for a 4 core U54 SoC with minimal peripherals. And if you can stuff it in a laptop form factor, it's portable.