The right wing extremists and neo-nazis live in East Germany because the soviets thought they were immune to fascism simply because they equate anti-fascism and communism. They thought their job was done by doing nothing. West Germany took significantly more cautions to prevent a rise in right wing extremism than East Germany.
If you would actually inform yourself a bit before spouting such nonsense you would know that East Germany was actually a lot more serious about denazification than West Germany after WW2 (not quite as serious as the official propaganda would want you to believe of course - for instance the early "inofficial" East German army made use of Wehrmacht officers until they were kicked out around 1956 when the NVA was officially founded, but still more serious (and effective) than West Germany which mostly turned a blind eye towards higher ranking nazi officials in the government, secret service and army).
Also the leading neo nazis who built up their East German networks in the 90's were mostly "Alte Kameraden" coming in from West Germany (and that's still the case, guess where Bjoern Hoecke grew up, hint: not in the GDR), and this was made easy not because the East Germans were "preconditioned", but instead disillusioned and frustrated with how the reunification was going in the 90s. The poor, disillusioned and frustrated tend to turn towards extremism, that's the problem in a nutshell, and that problem is not unique to East Germany.
