I've just watched the series and also read the Guardian reviews, which were less than complimentary; quote - " this terrible mess is a one-way ticket to Triteland".
Sorry, this is pseudo-intellectual snobbery.
Yes, the dialogue and the characterisation was a bit clichéd. But when you are dramatising nazis, how can you be anything other than clichéd? Not many shades of grey in nazism. It's more of a mistake to try to present a balanced argument.
I would admit that modern debate is binary and lacking in nuance, but for this drama, the message was far more important than the subtleties.
Better that your heart is in the right place than your head is in the wrong place.