It’s a fair point. Maybe no one saw the big knickers connotation and I think the film bombed anyway. If it hadn’t tabloids would have picked up on late bloomers also being old ladies’ knickers for cheap column inches. So, no, I would say not automatic. Bloomers as errors is fairly obscure I would say - is US bloopers better known even in the UK? It is to me.
But to return to my original point, the Spanish and French ‘rules’ for capitals at least judging from the names of the Late Bloomers film there seem to be very straightforward - start the title with a capital letter alone.
I just looked up The Adventures of Priscilla, Queen of the Desert at IMDB and the French and Spanish titles conform:
Also Known As (AKA)
Las aventuras de Priscilla, reina del desierto Argentina / Spain
Priscilla - öknens drottning Finland (Swedish title) / Sweden (imdb display title)
Приключения Присциллы, королевы пустыни Russia
Ørkendroningen Priscilla Denmark
Harpatkaoteha Shel Priscilla Malkat Ha-Midbar Israel (Hebrew title)
Les aventures de Priscilla folle du désert Canada (French title)
Oi peripeteies tis Priscilla, tis vasillisas tis erimou Greece (transliterated ISO-LATIN-1 title)
Priscilla Japan
Priscilla - Königin der Wüste Germany
Priscilla, Rainha do Deserto Portugal
Priscilla, a Rainha do Deserto Brazil
Priscilla, a sivatag királynőjének kalandjai Hungary
Priscilla, aavikon kuningatar Finland
Priscilla, folle du désert France
Priscilla, królowa pustyni Poland
Priscilla, kraljica puscave Slovenia
Priscilla, kraljica pustinje Croatia (imdb display title)
Priscilla, la regina del deserto Italy