There is a very interesting book, D-Day Through German Eyes that is worth reading whether or not you are a WW2 buff.
Some of the things that stuck in my memory; German soldiers had never experienced White Phosphorus and were terrified (rightfully so), another was the description from Germans who were in tank turrets permanently affixed to concrete foundations a few thousand meters from the beach.
I suspect Brian got some of his German viewpoint from "D-day Through German Eyes". I read it (for free) on Kindle during our original lockdown. It was a fascinating perspective that was well written by a "military journalist" who interviewed soldiers on the Atlantic Wall in spring 1944 then went back 10 years later to find out how things actually went for them.
The author let the soldiers set the tone so you get a mix of repentance and bravado.
The Germans watching the Allies land in Normandy were confused, wondering where all the expected horses were.
(Let me recommend the excellent Kindle book "D-Day through German Eyes".)
I think I read that here
D DAY Through German Eyes - The Hidden Story of June 6th 1944 https://www.amazon.com/dp/1539586391/ref=cm_sw_r_other_apa_i_DZnWDb9CZ9EWB
If you’re interested, I definitely recommend these books.