I wouldn't call it confusing because the rules are very regular. Prepositions and articles are lowercase unless they start the sentence, the same rules apply to spelling in titles (eg. book titles).
It’s confusing because you have to know the nationality of a person to know how to capitalize their surname (In Flemish Dutch, prepositions that do not start a sentence are uppercase if they’re part of a name)
And nitpick: you likely meant “Willy Vandersteen” (https://en.wikipedia.org/wiki/Willy_Vandersteen), but that would be a bad example as it, I think, would always be capitalized, also if he were Dutch.
And nitpick: you likely meant “Willy Vandersteen” (https://en.wikipedia.org/wiki/Willy_Vandersteen), but that would be a bad example as it, I think, would always be capitalized, also if he were Dutch.