no it IS more accurate. When i am off-roading i always record my track and have to unplug my phone from the trucks system to get an accurate un-smoothed track.
google maps does weird things but gaia just uses the raw GPS data from the phone and doesn't snap, however when you are plugged into carplay the phone seems to always consider the car/trucks data more accurate even when its clearly not.
this could very well my specific truck (dealer has refused to look and i don't have another to compare to) or a general tacoma thing but it both smooths the GPS data to make "nicer" looking lines and often introduces drift over time as likely some processing it does compounds an error
(i also realize i said the wrong phone, iphone 14 not 12 but even with the 12 it was notably better then the truck but the 14 pro has a much improved GPS and it shows)