It's an overreaction after the Chinese "spy balloon" fiasco. Weather balloons snap their moorings fairly frequently or are free floating, and smaller balloons with radar mirrors are used by any number of nations and groups for all sorts of purposes, from meteorology to weapons testing. They float well above the ceiling of even military aircraft so they aren't a danger to planes. They are slow moving and tend not to be captured on early warning radar, and even if they are were usually ignored by ground crews who could see its clearly not a plane or missile.

But after the "spy balloon" and the US military and the White House making such a big deal out of it, and getting criticism for not shooting it down earlier. They probably have ordered the Airforce to start shooting these things down whenever it pops up on radar. The fact that they don't even know what they are shooting down is telling since they are probably only seeing radar blips. The original Chinese balloon was huge, and could be observed from the ground, simple weather balloons and radar reflectors are much smaller; the pilots themselves almost certainly can't visually see them before they fire their missile.

This is obviously worrying, becuase this kind of hightened alert is how you end up shooting down an airliner.