I don't think it's been possible for years. A person can write a cutting edge tech demo but it's not really usable as a general 3D engine. A small team might be

I don't think it's been possible for years. A person can write a cutting edge tech demo but it's not really usable as a general 3D engine. A small team might be able to write a limited 3D engine that would be state of the art in some circumstances.