Electrify America claims that on two cross-country interstates routes they already have charging stations 70 miles apart on average, with greater concentrations around major urban areas. This, of course, does not mean that there is always a charger within 70 miles of where you might be on these cross-country routes. Also, there are still large stretches of the U.S. that have no EA coverage. There are no EA chargers at all in North Dakota, and quite a few states (including some large ones such as Montana and Maine) have five or fewer EA chargers.
Also, in the 2018-19 timeframe Electrify America published a long-range plan consisting of four phases extending to 2026. Upon completion of this plan, EA claimed that you would never be more than 170 miles from an EA charging station at any point in the continental U.S.
With the adoption of an NACS standard and the continuing rapid expansion of Tesla's Supercharger network, I'm wondering if Electrify America will even be around long enough to implement its full four-phase plan . . . or whether anyone will care, as few customers with experience of EA thus far would program EA as their first-choice charging stop on a road trip if alternatives were widely available.