WetGeek
Although I've used instances of Vivaldi and (lately) Brave for my normal browsing tasks, I had never changed my default of Google Chrome. My reasoning was that if I clicked a link in an email, e.g,, an advertisement I wanted to see, I didn't want that to be blasted into a browser where I was working with a banking session, or trading stocks on my brokerage page. Or the sites I was streaming.
So long ago I had set Google Chrome as my default browser. For ad-hoc browsing like an ad in email, that's what I was using. And after looking at whatever the email provided, I'd close the browser. Definitely a one-off situation, whereas Vivaldi or Brave might be running for days at a time. In fact, on the media machine, browser sessions could last from one weekly update to the next.
Now that I'm using Brave for all my serious long-term browsing, I've set Vivaldi to be the default for those ad-hoc, one-off tasks. There's no Google Chrome on any of the machines here now.
I'm pretty sure that this sly scheme is going to backfire on Google, in short order. There'll be no way for them to keep it quiet, especially after all the other Chromium-based browser builders tell all.