You are not.
Choosy OSX as the main browser. This is just a proxy to launch browsers depending on urls, not an actual browser.
Chrome for Google Drive, Apps, whatever they call it today
Firefox for Whatsapp + Facebook and for websites where I need multiple identities via containers (e.g. company & personal Amazon)
Safari for everything else.
There some overlap, but the main goal is to not be logged onto Google or Facebook in my main browser.
I like to think my countermeasures work, but I am under no illusion that no one out there someone has a big fat fingerprint of mine.
I also use Next DNS and often route my connection to a Wireguard VPS.
Phew! Life's hard on the modern internet.