D&D is a particular subgenre of fantasy, yes. But that subgenre has very much become the default fantasy subgenre. If you say "fantasy" without elaboration, what almost everyone thinks of is essentially D&D fantasy. An elf without other elaboration is a D&D elf. A dark elf is a drow. A dwarf without further elaboration is a D&D dwarf. An orc if you don't specify, is now a D&D orc. Paladin, ranger, thieves' guilds in every city, the list goes on and on.
None of these things are D&D inventions, but the D&D version is the default assumption across the fantasy spectrum because D&D is the default, generic any-fantasy-setting until you specify otherwise.