Question on Engine sound when shifting - 2008 TRD Sport DC 183K mi

Hey guys have just a general question and forgive me in advance b/c I speak medical jargon all day and my truck/mechanical talk is suspect at best

My truck is making (to me) sounds of possibly some strain when trying to shift when i'm driving. I don't know if this has been sounding this way for awhile or if i'm just somehow noticing it more now that the roads are quieter during this pandemic. I have a 2008 TRD Sport Automatic Transmission with 183,000 and some change miles on it and have not had any other problems with the truck since birth. I recently took her in to the Toyota dealership last week for a V6 tuneup with spark plug change and they also performed an induction system cleaning.
Any thoughts ? maybe this is in my head. I don't know all the other maintenance performed and Intervals as i'm sure many will ask me (I know i've been a bad taco dad somewhat), but I've performed all the oil changes on time and i'm sure i've passed on some of those flushes and such that they've recommended to me at the other oil change places (not dealership).
- could this be transmission based? I don't know how to really describe what it sounds like other than it sounds like it's trying to change gears but not really progressing. the RPMs are remaining constant in low so it's not like they are showing high.

would an OBD2 guage connector tell me anything if I got one? was considering a Bluedriver. thanks guys.