This toxic negotiation tactic is in use when someone attempts to invert things that are positive about a negotiation, your organization, or you into something negative, often employing abuse or disrespect. This is common in narcissists, sociopaths, and psychopaths.
“This negotiation is pointless. Your small startup has no track record and you are wasting our time. In fact, it was disrespectful of you to even request this negotiation.”
The way to deal with this interaction is to remove the person from influence over the negotiation, organization, and yourself. Ask for them to be swapped out, or walk away.