While none of us can be perfectly objective, as von Forster notes, that does not preclude us from making observations that can usefully contribute. Bias is a terrible problem, stemming largely from hubris in science today, that does all too often produce irreproducible research. But it does not necessarily render us incapable of producing reproducible work. Not being 100% objective does not prevent us from contributing to understanding by creating falsifiable hypotheses.

Good science isn't necessarily right. Being provably wrong is really useful too, because it enables us to eliminate false hypotheses. We only need to be objective enough to be reproducible to be scientifically productive. Supposing that because we cannot be perfectly objective we cannot produce useful science is an impossible standard that demonstrably cannot apply to human endeavor. All we need to do is be reproducible, and that can be possible even if we are biased, as long as we are not so biased that we proceed to make assumptions that prevent testing our hypotheses.