I don't think that's an accurate way of saying it, and that a better way is that "Solvespace doesn't have tools to generate fillets and chamfers. The developers have shown some limited examples, but adding full-featured tools would be very difficult."

https://github.com/solvespace/solvespace/issues/149

https://github.com/solvespace/solvespace/issues/453

https://github.com/solvespace/solvespace/issues/577

edit: dang, got ninja'd by one of the devs in the cited threads!

It's on the radar. As has been discussed many times, a general edge modifier tool is a long way out for technical reasons. I was working on adding Chamfer/Fillet/ and Draft Angle to straight extrusions which will cover many use cases. But even that needs a bunch more work.

Old comment: https://github.com/solvespace/solvespace/issues/453#issuecom...

Could you provide a bit more detail about this? I haven't tried it, but I would expect that you could just define another surface with a such-and-such borders and such-and-such curvature?