You can probably safely assume the 3-letter agencies are snooping on this data. It is and has always been very hard to resist government pressure. Happens all around the world, China, Russia, EU; all the geopolitical players find various means of eavesdropping where they can.

Also likely part of why ECH is taking such incredibly long time to see widespread adoption and why it's still quite a shit solution to SNI. As it stands, anyone with network level access can see which websites you are visiting, despite HTTPS.