Why cap it at all?
replyIf you can process 512 then you get access to those, else you don’t.
Let the free market decide where it’s comfortable like it did with wireless security.
What good is a standard if it doesn't make devices interoperable?
replyCatcher pitcher model. Pitchers pitch, catchers decide what to catch. You want access to the 512 space, pick up the 512+ capable device.
replyFree market decides where it lands.
If there’s nothing of value at 512, it’ll naturally flop.