Chrome is heavily promoted on some of the most high traffic websites. Users of those websites are told they should use Chrome. So they do. There's nothing Mozilla can do about that. Mozilla doesn't enforce antitrust. No upheaval within Mozilla will change it.
It is not a very conspicuous signal. I don't know which one of my friends use Amazon Smile. I don't think the dark pattern would work well if Amazon Smile was only social signalling. Seems to me it relies much more upon the fact that actual money is given to charities. Pretty gross of Amazon to add unrelated self serving conditions to such giving.
I can't say that I like the wikipedia reminders, but I don't dislike them. They remind me to pay for a service I use daily. So I do and they don't remind for a while. It is fine.