I always thought that parable had to do with those believers during the Tribulation. With the Age of Grace ending, folks will have to resort to works plus faith based salvation again.
https://gracethrufaith.com/topical-studies/parables/the-parable-of-the-ten-virgins/
Interesting ... the five who were busying themselves ‘working for oil to put int heir lamps, well they will be the Tribulation workers too. The aspect of oil in the lamp though is an analogy to The Holy Spirit within the human spirit. Think the Holy Place with the golden lampstand and the oil for light therefrom.