I thought I would share as this has been plaguing me for several months.

TLDR - I replaced the Engine Temp Sensor and my bike is good to go (so far)

Longer version:
My 2016 Street Glide Special was having what I would call Idle Issues starting in May (2023)
Sitting at a stop light, the RPMs would jump up to 1500ish and/or drop to 500ish. When doing so, letting out the clutch and/or twisting the throttle would have the bike coughing or stalling
I figured out how to get her going, she'd cough a bit, but get going. Once she was moving, I was good. But I could still feel a bit of hesitation when shifting into 2 and 3, but she shifted and accelerated...so I was good enough
She has stalled when stopped at intersections. Would immediately restart OR a few times wouldn't which would require me to push her to the side, give her a few minutes, and then she'd start.
When downshifting, twisting the throttle (to rev match), I would get zero response.
Sitting at light, I could quick twist the throttle and get struggle or coughing.
But never consistent! I could ride miles with zero issue and then randomly have this issue. OR I could go for a ride and have this issue be persistent through the entire ride.

The quick answer here, I found a reference to a similar issue on a forum in a Road Glide page, the Engine Temp Sensor was the fix.
So I tried it two weeks ago
I've covered 700-ish miles sense, in all kinds of weather (hot, cool, rain) and NO ISSUES!
I think she's good to go.

Along the way, I cleaned the throttle body twice. I cleaned the MAP Sensor, and the replaced the MAP Sensor. I diverted the oil blow back to a tube exiting under the bike. I replaced the Air Filter with a K&N Air filter. I was on my way to considering replacing the Coil Pack. My buddy checked various electrical outputs and was good to go.

I wanted to share, in case someone else found themselves having "idle issues".
Maybe a $45 Engine Temp Sensor will be your fix as well.