while doing some winter cleaning, noticed one of my pretty new reels (daiwa tatula type-r) thumb bar is quite clunky and much harder to disengage when pressing to release the spool compared to all of my other reels. something definitely seems off i've used this reel a maybe twice. any idea what would be causing this?

A quick-check thing to try is to depress the thumb bar, then put a bit of oil on each side of the thumb bar(thumb bar pads) where they meet the frame. Cycle it a few times. If nothing changes you'll need to pull the gear side plate to lube the clutch mech and kick lever trough. 10 minute job. Might as well grease the gears while you're at it.

If it works I wouldn’t worry too much. It’s rather common for identical reels to feel a little differently. Lube it up and just keep an eye on it. 

It could be a part is slightly out of tolerance.  Or maybe a lube issue.  Hard to say without taking it apart and examining it in person.  If it's a tolerance issue, it'll often sort itself out with some use.  

6 hours ago, Bankc said:

It could be a part is slightly out of tolerance.  Or maybe a lube issue.

Some Daiwa CTs were delivered nearly bone dry. Type Rs haven't been produced for a few years, so throw shelf time into the mix. If stored in heat at any point, whatever grease that might've been present could've easily migrated away from where it needs to be.