That's only while Google graciously allows to disable it at all. When Google will decide to make Floc permanent, these Chrome mods called Brave and Vivaldi will be forced to do it too.
it's actually been completely removed from brave nightly as the link says
how will they be forced?
When Google will remove ability to switch Floc on or off from the code of Chrome browser and all it's mods.
They have their own builds.
Brave would hard fork Chromium rather than go along with something like that
I've seen enough corporations in my life to understand that unless we are talking about PR disasters (and Floc is not it) it is more convenient for corps to spin up some short announce why it something is actually "good for you" instead of doing hard to do and expensive actions like real code fork. People will grumble a bit and forget in a week.