The dynamic navigation was introduced for the RAV4 with the 2021 model year. Those who have 2019 or 2020 RAV4s do not have dynamic navigation.
The way that the dynamic navigation system works is that there is one set of map data that is installed in the car, but, when you want to enter a new destination, before giving you directions, the system searches the cloud to see if there is any updated map information or traffic information, and, if there is, the system uses that updated information to determine the directions that it gives.
Once your 3 year free trial ends, you have 3 choices. You can pay for a subscription that will allow the dynamic navigation to continue working. You can pay for a map update that will install a new/updated version of the map data in your car. If you chose to do that, the new data will be used to set the system's route, and it will not check with the cloud to see if there are any new updates. Or, you can just let the dynamic navigation system expire and pay nothing. If you do that, the system will revert back to the map data version that was installed in the car when it was built, and it will operate just like navigation systems have operated for the last 20 years or so with whatever map versions were installed when the car was built.
Also, I believe that traffic information comes via HD radio station signals. If there are no HD radio stations where you are driving, traffic information will not be available.