This is true, I have first-hand knowledge on Bulgaria

NEVER enter a taxi in Bulgaria that isn't marked, or they will take you for 50-100 euros.

NEVER drive in buses from Sofia to the coast in summer. Big convoys of mafia wait for buses with western tourists, stop them and rob everyone inside then let it go when they're with nothing.

German Turks driving down from Germany drive in convoys of 10-20 cars at once because they are almost guaranteed going to be robbed if they stop at any point in Bulgaria. Even turks know how subhuman Bulgarians are.

There are generally 2 shitholes in the balkans: Albania (by extension kosovo) and Bulgaria. Ex-Yugoslav republics are the white civilized ones. Albania, Bulgaria and parts of Romania are 3rd world and will remain so due to the gypsy infestation.