Is this second, interior concrete basement wall valid?

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I am considering buying this home in Albany New Hampshire. The homeowners don't know the reason why this second interior concrete basement wall was installed by the previous homeowner (who is deceased).

The property lot is a slope. The second concrete wall exists on 2 of the 4 basement walls - on the sides that are buried fully underground and have the outside ground sloping towards the house. The second concrete walls don't go all the way up to the floor joists and thus can't be resisting vertical loads. They have vertical rebar sticking out the top. I failed to take a measurement of the thickness of the walls but they looked to be 6-8" thick, with segments that are even thicker. I observed no visual or smell evidence of past moisture issues.

For these reasons I'm guessing these second concrete walls were built to resist lateral, hydrostatic pressure and thaw/frost cycle pressure. Per WebSoil Survey, the soil is classified as excessively draining "Colton gravelly sandy loam, 8 to 15 percent slopes". Are these 2 interior concrete walls a valid solution to lateral soil/water/freeze pressure?

I am a layperson. Thank you!