poetry export - should it include optional extras by default?

What is the intention for poetry export with respect to default behavior for optional dependencies? It seems to include them in the output requirements.txt file.

poetry export --without-hashes --format requirements.txt --output requirements.txt

For example, if scipy is an optional extra, it should not be in requirements.txt (right?)

scipy = {version = "^1.5.3", optional = true}

But, there it is:

scipy==1.5.4; python_version >= "3.6"

Given there are additional command options to include optional extras, it suggests the default behavior is to exclude all optional dependencies (unless explicitly requested with an --extras {x}).

Could it be that a dev-dep for e.g. seaborn has a dep on scipy and the poetry export is not filtering out a dep of a dev-dep when it exports? As in python-poetry/poetry#3448 ?

Reproduce the poetry export --without-hashes --format requirements.txt --output requirements.txt command with scipy marked optional, then compare the output with an explicitly requested --extras case. Trace whether scipy enters through the optional dependency itself or through a dev dependency such as seaborn; done means the intended default behavior is established and the export behavior or documentation matches it.