Boycotting is an expected/intended tool in capitalism. It’s part of the “free market” philosophy, the regulatory “invisible hand”. The reason you can boycott a company is because the economy is based on a capitalist free market.
If boycotts were actually a good and successful method for the society to regulate the wealthy, then there would be no issue with capitalism. So that’s not how you “end” capitalism, that’s just how you make it work.
The issue is, precisely, that boycotts do not work (and thus, capitalism does not really work). Particularly when entire industries are controlled by private de-facto monopolies. If they worked you would not need social-democratic laws to force companies into compliance in many ethical aspects.
What you are advocating is not an alternative to capitalism (like communism or socialism), but a more ethical/educated capitalism that works at controlling the wealthy, just like many proponents of capitalism expected it would.
That’s even harder. Specially if we aspire to have a community that protects privacy & anonymity.
Keep in mind “rich” does not necessarily mean “famous”.
For all anyone knows, you and me could be part of the wealthy, yet nobody here would know, no online service would deny us service. Being forced to live an anonymous and private life is not really much of a punishment, at least it wouldn’t be for me… if I were part of that wealthy I’d just lay low… I’d get a reasonably humble but comfortable house in a reasonably neighborhood where people mind their own business, dressing modestly and living life without having to “really” work a day of my life, while my companies / assets / investments keep making money so I can go on modest trips and have some nice hobbies that are not necessarily really that expensive anyway. Anyone who figures it out, I set them up. It’d still be worth it to live that life.