A US citizen married to a German, sitting in Berlin, employed by a German company, paying German tax and with no affairs in the USA, should not need to be burdened by the IRS's reach.
The US citizen sitting in Berlin, employed by a German company, paying German tax will almost always pay no US tax due to both US law (up to $90,000 abroad income is tax free from the start) and tax treaty agreements with Germany. The only "burden" is filling out their 1040 tax return (and necessary attachments). US citizen in some other countries without a Social Security (SS) agreement do have an extra "burden". But quite frankly, I have no problem paying into US SS since it offers better returns than what one will ever have here in Hungary.
In short, because I do have benefits from my US citizenship, I see paying any required US taxes as perfectly okay.