There is actually a fair bit of discussion about prebuilt ebikes here, and it would be handy to be able to stick it in it's own subforum. Some I can think of without looking are the SurRon, Stealth Fighter and Bomber, Prodeco (though it's no longer made), Stromer, Frey, Motorino, etc. I could probably find a dozen others without trying too hard.
THen there are all those that come here to fix their prebuilt ebikes and other stuff. Do we tell them to go away because they didn't build it themselves? No, we help them figure out what they can do, whether that is get OEM parts or do DIY fixes, etc.
How about those posting about their prebuilt large EVs, like Teslas or Nissan Leafs or Honda Insights, etc? There's not a lot, but there have been some--and some of those with them have been active helpers here on the forum over the years.
Used to be a lot of esk8 discussion, including prebuilt boards (sometimes about modding them) but something happened that I don't really understand fully and they all went elsewhere, so we lost a bunch of nifty DIYers to that.
Keep in mind that if people came here to discuss prebuilt stuff, they can also be "influenced" into more DIY, and you may find some serious DIYers, engineers, programmers, etc., in those riding prebuilt bikes that just haven't gotten into modding that bike yet (perhaps they haven't even thought of it yet).
Or they make enough money at their dayjobs they don't need to DIY something and can buy whatever they want.... But might be contributors here if they were already posting here for their prebuilt stuff.
Heck, if I had money for it, and someone actually made the bikes/trikes/etc that I need, I would just buy one rather than go thru the years of development to make one work for me. But I'd probably still be here helping out...unless I wasnt' really welcome to post about my prebuilt stuff, in which case I'd be someplace else, or just keeping my time and using it for more fun things than helping people that often don't seem to really want to be helped.
I would guarantee that there are others like that here now, and plenty more out there that aren't yet, but could be.
So...I don't really get why we would want to alienate anyone that's into EVs...even if they didnt' build the one they have now.
At it's simplest, it could just be a single forum heading for "Pre Built / OEM EVs of all sizes and types".
Dividing it up into ebikes, escooters, esk8s, emotorcycles, large-EVs, and other-EVs might be helpful, but perhaps not required until there is enough traffic to worry about it (though I would do it to start with).
If we don't make a subforum for them, do we then remove all discussion about them that is already ongoing? Do we remove all the sellers for such things? Do we just lock all those threads? Do we just let it go on as it is now, just buried in the midst of all the other stuff? Do we draw the line at "i bought it but I want to modify it", or is anything prebuilt disallowed? Etc.
I ask this because the way LeftieBiker's question was answered makes it sound like anyone that rides prebuilt stuff isn't welcome here at all. That might not be the intent...but that's what I felt when I read it.