On 16 Feb, 12:30, lonelytraveller
wrote:

But the Victorians didn't have escalators, so why would there have
been a passageway in that particular location? Its parallel and next
to the passage between the bakerloo line and the northbound northern
line platforms, so it doesn't seem to be purposeful.

Don't forget that most deep stations had lifts in the beginning.
Staircases were converted to escalator machine chambers also.