It is honestly ridiculous to even discuss TB2/3 or Anka, any of our other MALE drone going up against a jet. Unless it is a freak incident, like when a Russian jet tried to down a TB2 in its wake turbulence, it simply isn't going to happen.
What a MALE drone with a2a missiles can target is: other MALE or HALE drones, helicopters that ventured too far from anti-air protection, (depending on the radar and targeting) maybe slow moving cruise missiles and big kamikaze drones. Now, we obviously have other anti-air measures against all those targets but that is where the term "layered air defence" comes in. A drone with a2a missiles is just another layer of protection on top of the existing ones.
It is like a "better safe than sorry" approach to air defence, drones are not that expensive and missiles like Sungur are relatively cheap, so why not have one more layer when we can easily do it?