You're very confused.
East Germans athletes took drugs. Period. That has nothing whatsoever to do with whether or not athletes from other countries took drugs. Those are two separate things. Your thought process doesn't work very well.
And no, I am not naive at all about the drug use in the 1980's by athletes from many countries, or the drug use by the top Chinese women in the 1990's, or the EPO use by many distance runners in the 1990's.
However, none of that changes the fact that the East Germans had a state sponsored drug program for their athletes.