Here’s wiktionary:
Although sometimes used, normalcy is less common than normality in American English. It is very rarely used in the UK, Canada, Australia, and New Zealand. It is frequent in India and Zimbabwe however.
So it’s a regional thing.
Although the claim that in US English the “normality” form is more common does not match my experience as a speaker of US English.
“Rollenden Königlich”? Ist das wie “Rolls Royce” auf Deutsch heißen soll?