Previous owner pinned the transmission thermostat open and left it

Bought this 2016 Tundra recently. Was installing a RCI skidplate, when I noticed this:



Looking at the records, the previous owner had a smaller service place replace/flush the transmission fluid in July 2022, and it looks like they forgot to remove this. So he has been driving it for two years pinned open.

From reading several threads on the matter, it seems some people pin theirs all the time, or pin it in the warmer months and remove the pin in the cooler months.

I assume no harm can be done by leaving it pinned for the past two years?

I pulled it.

 

With the transmission cooler pinned open, the transmission may warm up slower. That’s about it.