I can just about guarantee it has nothing to do with targeting and a lot to do with making Venezuela unsure when strikes are about to start, both for security of the forces launching the eventual strikes (if any) and to harass/wear-down Venezuelan air defenses by keeping them very alert.

If our aircaft were flying transponders-on during all these exercises then suddenly went dark, it’d signal imminent attack. This keeps them guessing. Possibly we’re even playing around with having them on some of the time for some aircraft, and off at other times.

We don’t do that with AWACS and such near Russia because we’re not posturing that we may attack them any day now, and want to avoid both accidental and “accidental” encounters with Russian weapons by making them very visible. In this case, an accidental engagement by Venezuelan forces probably isn’t something US leadership would be sad about.

I live near JBLM in Washington. I am routinely overflown by helicopters and planes (C-17s) often with their transponders off (I have an ADS-B receiver running on a VM). These are training flights that are not going anywhere outside of the Puget Sound region. For added fun, I'm also pretty close to several Sea-Tac approaches.