Is the IETF a homologating authority?
Or what is really meant by the publication of numerous “RFC” standards with language of MAY, SHALL and SHOULD?

When internet standards have been officially published and promoted by a government, we say that such standards have been promulgated by the government. This is unquestionably so, even though this is not language typically used by governments to describe their own activities.
We are getting mixed signals, together with a suggestion of military authority and occasional enforcement from the Pentagon. Typically the next step after promulgating a standard, and accepting comments and discussion on it, is termed homologation. The language of MAY, SHALL and SHOULD implies homologation, but the retention of the letters RFC (Request For Comment) denies this. The complete process of standards-making on the internet was supposed to be cut short of an overreach of government authority by pompous incompetent meddlesome ingratiating bureaucrats.
The status of any published documents as “Official Internet Protocol Standards” implies that such standards have been legally (but not lawfully) homologated by the federal government.
[Note: This maturity level was retired by RFC 6410: "Any protocol or service that is currently at the abandoned Draft Standard maturity level will retain that classification, absent explicit actions."]
Homologation of technical standards is inevitably corrupt and carries adverse legal consequences in various civil rights and international contexts, including significant civil liability and criminal culpability. Certain private businesses stand to profit and others stand to lose money as a consequence of homologation of various technical standards. Some computer software (especially cryptographic software) has even been made subject to import or export duties (as tangible goods like alcohol, tobacco or firearms with the associated bribery of public officials) by the homologation of standards even if such software is otherwise freely distributed as open source code.
We’re at a point now where the government has re-cast or reinterpreted and all but trademarked the letters “RFC” as a full homologation or officious rubber-stamping of the documents as official government standards, while at the same time attempting to deny the social, legal, political, diplomatic and military consequences of homologation and corruption by the federal government.
There’s a patent office for private standards promoted by private parties pursuing profits from the same, in order to permit such limited vice to encourage them to bring out the technical details of their inventions for public discussion and review.