Everyone is correct here but saying it differently.
Maybe I can further confuse things: :)
Roon consists of three parts:
-Roon Server this is the computer that runs Roon Core
-Roon Endpoint: this is the streamer or bridge. A Roon Ready or Roon Certified streamer typically will run Roon AND may have its own software to run Music. (examples are Aurender has Conductor App, Auralic has Lightening app, etc etc.
-Roon Remote: this is how to control Roon, usually an iPad or iPhone etc.
Now there are also Roon Bridges. These typically run Roon but no other music playing software is offered.
I believe the Rendu's are Roon bridges, where they combine a computer to run Roon Core and also stream music using Roon (but I am not familiar with these products).
While you don't need a dedicated (separate) streamer if you have an internal bridge, many find a separate streamer will sound better than a bridge imbedded in an amplifier or preamplifier.
I have a MM Tambaqui. It has an internal Roon Bridge and is Roon certified as an endpoint. But when I got a dedicated streamer (Auralic Aries), it sounded better; More organic and lifelike. Now I also have a Grimm MU1. It Runs Roon Core (Server), and also is a Roon endpoint. It sounds very very good streaming to my Tambaqui, but offers no other music software than being a Roon Endpoint. But it is as good as most two box setups, a Roon Core and A Roon Endpoint (bridge).
Finally, to actually answer your question, any streamer or combined server / bridge that is Roon Certified or Roon Ready can output music to your DAC. It may do this with USB, AES, Coax, Optical, I2s or any combination of these things. So a
DAC does not need to be a Roon Endpoint. But if it is, it has an internal Roon Bridge or internal Streamer.
Happy Holidays!