Those minimums are taken from Docker. The person above asked why they were what they were, I answered. You're just further reinforcing what I explained.
Running something in a Docker container adds very very little overhead - to the point that it's almost immeasurable. The resource utilization is specifically because of the services that have been packaged in the containers.
If you were running the Bitwarden server on bare metal (which you can definitely do), the requirements would still be the same.
HN has reached the point, that it will heavily downvote an objective fact because it goes against the pointed narrative. They took a dependency, copied its system requirements, and someone asks "why?" and that is the actual answer.
A lot of the other answers (multiple Dockers, slimmer image) really address how Docker themselves have these exact system requirements listed, but why do they need to when the point isn't to answer the actual request asked by get lost into a predisposed critique.