I don't think that the "MAX type" has been revoked.
https://www.faa.gov/aircraft/air_cert/airworthiness_certification/
The Boeing 737 MAX Certification
The Boeing 737-8/9 Max design had minor changes to the 737 Next Generation (NG) design. For this reason, the FAA issued an Amended Type Certificate to the Max airplane,
which was based on the Type Certificate of the 737NG. The FAA spent approximately five years certifying the Boeing 737 MAX. Boeing applied for certification in January 2012. The certification was completed in March 2017. Amended type certificates typically take 3-5 years to complete. By comparison, the certification of a new aircraft type can take between 5 and 9 years.