Which does absolutely nothing if your device or the app in question is permitted or otherwise not prevented from making DNS-over-HTTPS (or, less commonly because of its discrete port, DNS-over-TLS) queries.
Even some of the most popular desktop web browsers are configured to utilize DoH by default nowadays.
The most that a network administrator can do to prevent this is configure firewall IP blocklists of known DoH servers and NAT all outbound 53 (and 853) traffic to a desired resolver (like a local Pi-hole instance, for example).
A firewall (which must also host a resolver) can choose to block requests to IPs it hasn't resolved domain names for.
This is something I implemented for an Android firewall app I co-develop; it works nicely enough.
A firewall (which must also host a resolver)