The character of society as constituted

Hello, everyone,

"So excavation is invention/discovery or sculpture where archaeologists craft remains of the past into forms which are meaningful. The archaeological ‘record’ is, accordingly, not a record at all, but made, not given, ‘data’. ‘The past’ is gone and lost, and a fortiori, through the equivocality of things and the character of society as constituted through meaning, never existed as a definitive entity ‘the present’ anyway. An archaeologist has a raw material, the remains of the past, and turns it into something — data, a report, set of drawings, a museum exhibition, an archive, a television programme, evidence in an academic controversy, and perhaps that which is
termed ‘knowledge of the past’. This is a mode of production."

* source; https://books.google.co.kr/books?id=g3MeAgAAQBAJ&pg=PA12&lpg=PA12&dq=%22The+past%E2%80%99+is+gone+and+lost,+and+a+fortiori,+through+the+equivocality%22&source=bl&ots=ueV83Jkr0U&sig=ACfU3U1TPwUtMHvVOineJlXMDH3NaR7HNA&hl=ko&sa=X&ved=2ahUKEwiP6dSPjt_uAhUEMN4KHdaXCPUQ6AEwBHoECAQQAg#v=onepage&q=%22The%20past%E2%80%99%20is%20gone%20and%20lost%2C%20and%20a%20fortiori%2C%20through%20the%20equivocality%22&f=false

My question about the above underlined sentence is why ‘is or was’ for passivization has been left out after ‘as’, while I know well the case that the ‘be’ is optional in idiomatic expressions and in related with verbs – regard, see, consider, report, etc. as follows;

• As (was) intended, I arrived at 8:00.
• As (was) discussed in Asian History, the territory of China extended...
• ... competence as well as a socio-linguistic context (knowledge of the ... language skills so that the rights of the patients are not seen as compromised,
• ... as poor spelling and grammar, or checking link addresses before clicking them by ... and alerts you when a site's security has been reported as compromised.

However, while in the underlined sentence I don’t find any factor to trigger the deletion of the verb - ‘be’, will appreciate if you let me know what I’m missing.

Waiting for your various guides and RGDS,