Next-gen DMs use giftwrap to hide all their metadata. But that presents real problems especially for relay operators. For example, see this thread:
nostr:nevent1qqst06dfxc9dyjz6ak3ksear39xae5we6sukg95nmt0xv9ykkwavdespremhxue69uhkummnw3ez6ur4vgh8wetvd3hhyer9wghxuet59uq32amnwvaz7tmjv4kxz7fwv3sk6atn9e5k7tczyw0fg
Current-gen DMs don't hide metadata, and don't have the greatest security.
