No — "or" is lowercase in the middle of a title in most style guides.
"Or" is a coordinating conjunction and is consistently lowercased in the middle of a title across all major editorial style guides except Billboard Style.
In AP Style, Chicago Style, MLA Style, NYT Style, and AMA Style, the rule is clear and consistent: coordinating conjunctions are lowercase in the middle of a title. "Or" has no special treatment that differs from "and" or "but."
When "or" appears as the first word of a title — sometimes used for dramatic or rhetorical effect — it is always capitalized. The first-word rule overrides the conjunction rule in every style guide.
Billboard Style capitalizes every word, so "Or" appears in uppercase in music titles, advertising copy, and entertainment industry materials.
"Or" is treated identically to "and," "but," and the other coordinating conjunctions by every major style guide. It is a function word that connects clauses or options, and style guides uniformly reserve capitalization for content words instead.