A factory reverse camera only shows you anything when the truck is in reverse. That is fine for parking and useless in the two situations where a camera actually earns its keep: creeping over an obstacle on a trail where you cannot see the ground past the bumper, and checking a trailer or a blind corner without craning around. An anytime kit removes the reverse-gear restriction so the view is there on demand.
There are two kinds here. The front-and-rear kits add a forward-facing camera alongside on-demand rear view, and they cover the 2014-2019 and 2020-2023 Tacoma, the 2014-2019 and 2020-2024 4Runner, and the 2014-2019 and 2020-2021 Tundra. The rear-only kits cover the newer platforms: the 2024 and newer Tacoma, the 2022 and newer Tundra, the 2022 and newer Sequoia and the 2024 and newer Land Cruiser.
Everything displays through the factory screen rather than a stuck-on monitor, so nothing is added to the dash and nothing needs unplugging. The wiring is not identical across generations, so check the individual product page for what the kit includes and how it integrates on your exact vehicle.