FreeCAD and Dune3D are both OpenCascade based, so they are limited by OpenCascade's architecture (For example, OpenCascade uses per-entity tolerances, which means it is more bad geometry import tolerant, but if every face and edge has its own tolerance value in the kernel representation, then it creates a great amount of hidden tolerance drift.)

SolveSpace is still fairly limited on what it can do in terms of features such as fillet/chamfers, so it's not really suitable for pro work right now

For projects like SolidCraft, the SMLib kernel they are currently porting to Rust from Nvidia is currently about a decade behind OpenCascade, nevermind Parasolid/ACIS as they are still converting all geometry to NURBS instead of preserving analytical geometry, which means that their initial development is easier but it creates a near infinite amount of edge cases once they start going heavy into booleans and fillet/chamfers.