Yep, I call it out since the siding should not be in contact with the shingles. I see the trim boards rotted out all the time. BUT the hole has to be closed. I suggest metal flashing just like they put behind the siding.
If the gap is close enough to keep out vermin, it will also close enough to let water wick up into the trim boards and prevent them from being painted. Even Hardi board says to hold it back of the shingles.

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Jim Luttrall
Mr. Inspector.net, Inc.
Allen, Texas 75002