In short: Google has confirmed that the Pixel 3 does indeed support Daydream, even though the listing on the Google Store for the Daydream View only lists up to the Pixel 2 as being supported. This means that if you already own a Daydream View, you can still use it with the Google Pixel 3. This isn't a huge surprise, given that the hardware requirements that are public, are all included in the Google Pixel 3 - which include at least a 1080p display and an AMOLED panel. The Daydream View still costs around $69, even though it has been available for two years already. Surprisingly, Google has not discounted the Daydream View yet.
Background: Daydream View was the first - and so far, only - Daydream-compatible headset that it has made. Essentially, you can put your phone into the headset and experience virtual reality from your smartphone. This is why the display requirement is so important. OLED panels are better for Virtual Reality, seeing as you are getting better colors, and black blacks instead of them being gray. Of course, resolution is also a big deal, since you have the phone so close to your face.
Impact: The Google Pixel 3 support Daydream is definitely not a surprise, but it also shows that Google isn't giving up on virtual reality or Daydream. And that could be something people were worried about, with Google closing down many products the past few months. And with Daydream not having many announcements itself in the past couple of years, it does seem to be on the brink of being sunsetted as well. But the Pixel 3 does support Daydream which is definitely nice. So you can pick up the new Pixel 3, which starts at $799, and also get a Daydream view, and go off into virtual reality and have some fun with the different games and apps available.