Under some circumstances bluetooth can have less input lag, then wired connection, see here:
https://www.reddit.com/r/RocketLeague/comments/8wvf9u/controller_input_lag_comparison_more_info_in_the/
But as already mentioned, it depends of the BT-Dongle, some are better, some ar worse.
It also depends of the used Controller. Some Bluetooth-Controllers do have more and some have less input-lag.
8bitdo Controllers for example (but there was a firmware-upgrade released, which reduced the input-lag a bit).