The important thing isn't to try to not signal things (which is of course impossible) but to be aware of the nature of one's own signaling and how it can impact the exchange of information and belief.

Look at this post by Robin Hanson: Smiles Signal. Nobody is arguing that smiling is bad. But if you think about it, you realize that if smiling weren't a signaling behavior, it probably wouldn't be visible to others. Awareness of the ten thousand ways these adaptations influence our behavior is a tremendous component of what it means to be a rationalist.

One should also beware of using "signaling!" as a fully general counterargument of the form:

 My opponent argues for position X. But in doing so, he is only signaling
high status. Therefore,
not-X.