Most experts seem to think that is unlikely because its payload was much larger than a weather balloon needs.

It's also got some sort of maneuvering system that you don't find on most weather balloons, or even on most non-weather high altitude balloons.

Generally, balloons either have no maneuverability at all, or they can go up and down. Since the wind often blows in different directions at different altitudes that gives the up and down ones some ability to control their course by going up or down to a layer going the right direction.

But in the winter in the US there isn't that much variation. Right now for example its blowing east from around 4000 ft to something like 70000 ft or more.

In the summer there is a lot more variation, so normally if you were trying to send a spy balloon over the US you'd want to do it in summer. Then you can use altitude changes to guide it or have it stay roughly over a target.

A huge maneuverable balloon in winter in the US is something special.