Then I think you are mainly arguing against
Berkeley's idealism. However, idealism doesn't seem to have much credibility these days.
Or perhaps you are arguing against
social constructivism. I guess I would consider myself a kind of constructivist, but I don't think you would find my version of constructivism to be particularly bothersome. If you took a geometry class, you may have learned how to
construct an angle bisector. That we construct the angle bisector does not contradict that it exists independent of our construction. Construction can be a method of discovery.