Note that even the Swedish spy plane is using Ads-b while flying along the baltic International border zone taunting Russia but the migs answering the taunt is

Note that even the Swedish spy plane is using Ads-b while flying along the baltic International border zone taunting Russia but the migs answering the taunt is not. Also flying dangerously close to the spy plane (10 m reported once). However the US spy planes are also mostly flying with the transponder on there.