I'm not sure, they explored the concept of travel and exploration with destination worlds with packs like Jungle Adventure but it seems to have been changed to worlds that we can live in now and we can also do smaller quests in some packs like Cottage Living.
And the whole concept of transportation is more or less... not there in the sims4, there is no time management needed when it comes to travel and if you need to move around in the neighborhood we are limited to bikes, boats and horses.
No cars, no public transportation, how our sims are able to move any longer distances is anyone's guess.