And there's Firefox Klar on Android. It forgets everything on exit. Some people call it a porn browser, but I've gotten used to it for general use when I don't need to log in somewhere.
For those that wonder, Klar is Firefox Focus with telemtry disabled by default. It is available on german speaking countries due to trademark avoidance with the Focus magazine.
This is how we should view all information we get from a company. If the product say organic, claim to be pure ingredients, recycled material, made in "COUNTRY", or any other claim, it is only just that. It is simply a claim that you as the customer has no way to verify.
Having seen how these things are implemented in the field, your lack of confidence is definitely well placed. Most of these things send your denial request to /dev/null