While I don't disagree in theory... practically there a number of services that have one "owner account" that represents an organization and a business needs to make sure they have control of that account regardless of personnel changes. PyPi and Rubygems are examples from an old job.
Even when a service, like Twitter, does have multi-user/multi-owner identities in some business plan this might not make sense for small teams.
Even when a service, like Twitter, does have multi-user/multi-owner identities in some business plan this might not make sense for small teams.