Some people are able to ignore full leg extension because they don't have (or don't need) to pedal as strongly with electric assist. My wife has her seat all the way down to get her flat foot position. Pedal forward designs tend to result in more sedate bikes, like beach cruisers.
There's bikes like the Day 6, which has what looks like a lazy boy recliner for a seat.
Sedate ? Not really. The Aventon Pace 500 is pedal forward geometry, and is anything but sedate. Also, the Magnum low Rider and Magnum Cruiser, Magnum Ranger, are pedal forward and many of those customers buying them, report how they love how fast they can ride and how comfortable they are on their knees. Electra has their pedal forward geometries too.
If someone wants to ride in a more lean forward position, then certainly the 700 would provide that posture. Some people who commute regularly prefer that. I find that most people coming in my shop buying ebikes prefer a more upright posture. I was only responding to the mention that he wanted to be flat foot while seated. For most geometries with crank more directly below the seat, that would put the seat 2" to 3" lower than it should be for proper leg extension if truly desiring 'flat feet' on the ground.
Yes electric assist can offset that from the perspective of not needing as much leg strength, and if it a very occasional recreational ride. Much more to it than that, iif a person wants to ride a lot more and not suffer injuries. (Back, knees, wrist pain, can all come from improper fit, and especially when it comes from a desire to be more grounded while seated).
Often older people coming in to buy ebikes complain about knee problems while riding. 7 times out of 10, it's due to improper seat height on their existing regular bike. I know other regular shops who make a very nice income because they focus strongly on proper fitting. In the ebike industry that fitting is often ignored, especially as evidenced by all the people buying sight unseen and unridden on line. One size fits all frames are more one like 'one size fits very few.' Ebike oems like Rad who are trying to unload product in volume and low cost, need that one size fits all approach. Good for their bottom line - not so good for the unsuspecting consumer. Multiple frame sizes are more costly, for the OEM, and require carrying a wider product mix.
Anyway proper fit is not just in seat height, but reach, and other parameters. Ever notice how widely body shapes vary ? Long and short torsos, different arm lengths. Even pelvis differences can have a big impact. Then folks try to compensate by seat choice and mess with that a lot. Going by a person's height or inseam is a very crude way to get the right fit.
It's frankly amazing to see how people have contorted themselves and say they enjoy their bike, over the years. Honestly in part that's why those bikes sit in the garage way more than they probably would have been, had they gotten a proper fitting. It's hurt the industry for sure. Suddenly now that there is all the assist front a motor, it's like everyone is back to enjoying biking, but still not necessarily doing their bodies any favors with poor fits. I can see it immediately when I go out riding and see so many other riders on their ebikes with terrible posture and position. But hey as long as they don't have to do much work, they have a smile on their face.