Ahh, I was mistaken. Libre is open source.

Having used autocad for nearly 40 years, I will say they stick it to their customers pretty fiercely. I still use 2010 with 3rd party software to get it to run on win10 at home. I do a lot of solid models and assemblies as well as technical 2D drawings and renderings.

FreeCAD is impressive, but it lacks an easy to use interface. NanoCAD and LibreCAD are not open source but are free and are both better 2D alternatives.