Comment by kensey

I don't think (and wouldn't hope) this would be a flag-day thing where we stop using CA trust completely all at once and only use DANE afterward. DANE would become an option, disabled or secondary by default, that users could choose to use as a fallback if CA-based TLS validation fails. Eventually as adoption increased and the critical paths got cleaned up, DANE could become the default primary, with a fallback to CA trust if there's no valid response to a TLSA record request. Eventually as CA trust fell completely out of favor for most uses, it wouldn't be necessary for many clients to support it at all.