Ah, thank you for that correction! I somehow got myself mixed up and thought that the Z186 foot was removable from the collar, and thus it wasn't technically necessary to replace the collar just to change the foot. Not sure when I got that impression but things make more sense now. Apologies for any confusion.
There are two points that immediately come to mind:
The first is that similar to my previous reply above to Len, if we believe the Nikon rep's reasoning here, then in my mind they've chosen a solution that forces almost everyone who uses their lenses to employ aftermarket components to mount the lenses to tripod/monopod heads, rather than "taking a side" and potentially saving a large portion of the users (but not all!) from needing to do so. I will admit I can see why that makes sense to some, and clearly it must make sense to Nikon. Obviously, as an Arca-Swiss system user, I'm somewhat biased in my opinion that supporting that format natively would be a better move.
The other point I would raise however, is that if we look at the options on the market, in my opinion there's a clear dominance of the AS system.
There are certainly some exceptions, but for the most part I believe it's
mostly only very cheap tripod heads or very specialized and niche heads that do not utilize the AS system, and nearly all of those include their own proprietary QR plates which can bolt to a 1/4-20 port. The vast majority of high-quality mainstream gimbal and ball heads utilize the AS system. And furthermore, if we look at the options for aftermarket lens feet from RRS, Kirk, ProMediaGear, Wimberley, Hejnar, etc,
all of them conform to Arca-Swiss spec. To me, this indicates an extremely clear market preference for the AS system, and any outliers would be no better or worse off if Nikon added AS dovetails to their lens feet, so long as Nikon continues to include 1/4-20 ports as well that proprietary plates could be mounted to.
I do hope it's understood that I'm not trying to argue with anyone on this forum personally. I know some disagree with me and I don't mean to come off as combative. Hopefully my comments are not interpreted in that way...if I had a Nikon rep available to chat with, no doubt I'd have them sick of me in record time!