Check marks are supposed to be an anti-impersonation tool to prevent scams and hoaxes using well known identities. Musk ofc is too stupid to recognize this and just thinks it's a status symbol that people will pay for. When people do not pay for it and fake accounts run wild it will cause reputational damage to twitter. This is especially bad for twitter since the two things it trades on are being "the place to know what an organization or famous person is saying" and the network effects that build on that.