There is a discussion as to whether the amount of time or the distance traveled generates the obligation to say Tefillat HaDerech. The reasons being either because travelling far could lead to dangerous encounters (e.g. travelling overseas in days of old), or that travelling certain distances between cities you could encounter bandits or wild animals (as the blessing itself states), etc.
This article goes on to say that:
We don't say the bracha in town, even though there are many car accidents also inside the city, because the blessing was established for travelers on the way, and only outside town does one fall under the category of a "traveler". But as soon as one is on the way, the dangers are immediate, and not a function of how much time is spent on the road. Therefore it makes sense to say the bracha immediately after leaving town, if traveling for more than 4 kilometers, even if for less than 72 minutes.
Since travelling large distances is immeasurably safer nowadays, could it be legitimate to revoke Tefillat HaDerech altogether? Change the nusach? Or only said under very specific conditions?
As an aside: It is good to pray and acknowledge Hashem's help in any situation we encounter and there could be grounds for saying the blessing in any case, even though we are not obligated. However, we don't make a yehi ratzon for all things that are potentially dangerous (eating, walking down the street, swimming, bunjee jumping), but the 'traveler of the past' was given the status of 'in danger', such that a special blessing was instituted. It seems like the metziut has changed considerably.
