While this is true, I've dealt with a sudden battery failure on my old model ebike (a kalkhoff from 2018 or so) and I can tell you that without any motor assis

While this is true, I've dealt with a sudden battery failure on my old model ebike (a kalkhoff from 2018 or so) and I can tell you that without any motor assist the bike might as well be stationary. It is quite heavy.