It is sad that once again we will be exposed to more criminals trying to steal our data. Memory encryption not only allows to secure memory from physical "cold RAM", but also prevents loss of encryption keys as it hides the content during transfer.
Why no benchmarks against pg_vector, DuckDB with extension?
For benchmarks you may just prepare Phoronix Test Suite module (https://www.phoronix-test-suite.com/) to facilitate replication on a variety of machines.
Unfortunately the default configuration poses significant security problems, allowing for sidestepping 2-factor authentication schemes, and sideloading of applications without user permission (!)
It seems like UpWork failed to do due dilligence, and now wants to get somebody to pay for it.
They frequently delay payments just because they await your validation after all.
So the fault is on their side, but they may try to twist your hand, since they are big company and you are dependent on them.