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The note/tone sounds similar to the "ding" sound on a passenger aircraft...just repeated quickly.

The aircraft chime reminds me of the Home Alone theme, but I guess they're not in quite the same key: https://youtu.be/g3H9cnQDdvM vs https://youtu.be/nPNNFa3jF3g?t=26

As I heard that, I had a flashback to the first moments in many rental cars in my life.

The seatbelt warning chime has been there since the early 70s, I believe.