I've done many 10's of thousands of kilometers on bikes and there is no way to compare the two in practice, even the very best racing bike can't keep up with an e-bike over a long distance unless the rider is tour-de-France level.
E-bikes add range, compared to what you would do on your own in the same time. That is what makes them viable replacement for a car, suddenly 60% or so of your car trips are within the range of the e-bike, and with this large battery for me that is more like 95% or even more. Since getting the second battery for the e-bike I haven't used the car more than twice (that's a few months). Car ownership has gone from being a 'must' to 'uneconomical' and no regular bike that I've ever owned had that property.
And that's before we get into the fact that without the assist I have a hard time to get started at all.
And "the weight saving is probably outweighing the battery", is completely untrue. The increased weight of an ebike is probably adding like 5-10 watts of drag on flat ground and maybe 20-30 watts on hills, while the motor is providing 250 watts of output. It's not even close to canceling out, that would be insane.
I would like to be able to make these trips 1) faster 2) with less effort.