That's an early turn signal switch. As you have discovered, the replacement switches have eliminated that extra wire and connector. The replacement switches have piggybacked that extra wire onto one of the connector pins in the 8 pin (nylon) connector, using a violet wire. It is connected to the connector pin of the blue wire (see pic).
If you look at the violet wire on the new switch, it goes to a contact (on the switch) that never connects with anything.
John
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