I don't agree with the second part of your statement. I don't think their days are numbered at all, and there is a big market for custodial services. The reality is, most people don't know and don't want to be in control of their own money. They want others to do it for them with guarantees that everything will be all right. That's the way we have been molded to think for hundreds of years. Don't use this forum and its members as your basis that people enjoy non-custodial services, multisig setups, and complicated airgapped systems. The average person doesn't want that responsibility and prefers something easier and more convenient. They are ok with less secure custodial services and their arbitrary rules.