Why is a repeating event whose last instance was from a long time ago showing up in my daily schedule?

I think you misunderstand how it works?
The scheduled date for your events is in this year. There is no instance, there is only the block with the information.
There will be no next instance of those events.
If you make them a task and then click them done, they will be changed to a scheduled date of next year, there will not be a new instance.

See also the discussion I had with someone here:

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