It’s not that amazing. To be a registrar, you have to pay $10k for the privilege, then pay for multiple audits that you must pass (if you fail them you do not get reimbursed), and then you get to profit like $2 per domain per year, and you have to maintain high availability server farms, pay for the electricity, pay for the sysadmins, pay for the audits every year etc

There’s a reason Google stopped doing it after they got their .google tld