"zero value" would be neutral. Eg, if you tell someone, "Try DuskDozerIM, let's message on there! I like this thing where doubletapping the emojis plays a fun random little animation". Then maybe this is "zero value" to them and their response would be "whatever, sure, let's try it".
What I'm saying is if you go, "Try DuskDozerIM, let's message on there! It's private and secure, the government and large ad companies and data brokers can't read your messages and harvest your data" then you evoque a feeling of suspicion (negative value) and their response will be "look, I already have like a thousand apps, I don't really want one more".
One additional way you can confirm this hypothesis is that almost everybody has given WhatsApp access to { all contacts ; all notifications ; all permissions } but if you sell them Signal with the "privacy/security" angle and watch them install it, you will notice they hesitate for a sec and then reply "no" to contacts, notifications and permissions, as if they're suddenly trying to inhabit the conspiracy-theorist-cum-privacy-activist mindset. Which they're uncomfortable with, and don't like. Negative value.