i guess it depends how much support and how long of a distance. if i use my motor just to help with hills, strong headwinds, or the occasional bonk the range is 300+ miles. not that hard to plan a trip with a charging stop every couple days.

my longest single ride in which i used assist was 118 miles and i only used 93wh of power.

so it really depends what you mean by "supported by e-assist." used sparingly rather than to increase speeds constantly the tech is reliable, mature, and only imposes about a 10lb weight penalty.