So currently only Edge users can filter what gets picked up by Recall by site, and Chromium users get private browsing mode blocked out of the box? In the article, the Mozilla rep they interviewed says that Microsoft didn't reach out to them or hasn't made available any documentation on how to get non chromium browsers to pick what gets included in Recall.
Even if this is something thats off by default and is encrypted if you do turn it on, boy would I never want to turn it on.