What is Android's Private DNS (DNS-over-TLS) feature and how does it differ from using a VPN for DNS privacy?

• A.Private DNS encrypts all traffic leaving the handset, and it functions identically to a VPN (the setting establishes a TLS tunnel that carries application payloads alongside the queries); the difference from a VPN is the absence of a remote exit address, and every packet stays on its original route: the privacy gain covers the whole session.
• B.Private DNS is an iOS feature, and Android ships a different control called Secure DNS that covers the browser alone (the Chrome setting applies to page loads, with native app queries left on the DHCP resolver); the difference from a VPN is coverage, and every non-browser lookup travels in the clear: an Android user wanting device-wide protection needs a tunnel.
• C.Private DNS forces every query through Google's resolvers, and the logs there feed the advertising profile (the setting offers no alternative host); the difference from a VPN is that a VPN lets the user pick a provider, and all DNS privacy is nominal here: the queries move from the hotspot to Google.