Just to address this item (in no way dismissing the rest of your post)
~...................... people who support AfD won’t find their problems solved should they cease and desist with all immigration. I don’t disagree with that, however this radical influx Merkel allowed and still wants more of isn’t going to help them at all either.
The AfD grossly exaggerated the number of asylum seekers that came in 2015 (far over 1 million according to AfD, opposed to the actual 890,000) and continues doing that to this day.
Of course more people have sought asylum since that year but the number per year is sinking. As such the first half of 2017 showed 90,000 while the first half of 2018 showed 78,000.
2019 (so far) showed round about the same figure as last year.
The vast majority is from war-torn Syria.
All that notwithstanding, the woes of the "East Germans" (IOW former GDR) date back practically to the time of re-unification. GDR industry, pretty much bankrupt by then, was effectively bought by West German investors for a pittance and most often closed down to avoid increasing already existing over-capacities or kill any potential competition from the getgo.
At the same time "the West" invested heavily into infra-structure and that in a manner that contractors made profits while none of the "blessings" benefited Joe the Plummer all that much. Marble staircases in the main railway stations and some of the most modern highway systems of the whole Republic are all very well, but pretty meaningless to tens of thousands who have lost their jobs and have little hopes of ever getting another one.
As a result, the young worked on the principle of "go West", in that process leaving most smaller communities to rapidly over-age.
In addition to which, pensions paid in the "East" were (and, despite gradual adjustments being under way, still are) of a lower percentage than what the average "Westie" gained. All on the premise that the cost of living is lower in the East (true) but the way things developed, "living" rapidly became a relative term.
Of course pensions had to be paid for by somebody and the gubmint was averse to put all of the burden on the Westerners to pull thru a population that had never paid into the system at all.
But that is actually where Germany
really failed their new citizens and their gripes are certainly justified, at least to some extent.
Nevertheless, East German xenophobia dates well back to long before 2015, in fact as far back as GDR times when the solidarity with socialist "brothers" brought Vietnamese guest workers into the workers' paradise.
To add some anecdotes of my own, when I was working in Germany I well remember the hostility with which Germans of Turkish roots were met in East Berlin just after re-unification. General attitude having been even then "get out you leeches, it's our turn now". This to people who had contributed to the German social systems far more than the "Easties" ever had (to do justice, had ever been able to) and were actually paying their pensions, their health care and, in case of job loss, their dole.
By all counts, having the advantage of a rich Western cousin to turn to and gripe over is not beneficial to one's own efforts to take responsibility at least in making rational assessments.
It also creates a fertile field for the rat-catchers to harvest.
