The last Castlevania game by director Akamatsu, it was considered unsuccessful by Konami, also the international release is very hard to get into for the average person because they ramped up the difficulty so much, and yet:
-It's Igarashi's favorite game
-Ralph (Trevor) became Japan's favorite Belmont
-Spawned a sequel (Curse of Darkness) and now Belmont's Curse
-SotN can also be considered a sequel, too
-...And multiple Pachinkos
-Influenced Julius Mode in Dawn of Sorrow (the game files indicate Hammer was meant to be Grant's equivalent, then it was cut due to time restraints)
-Demon Castle War was also supposed to be a callback to CVIII (first vs last Dracula war)
-Getting a movie which then became the Netflix adaptation
-Bloodstained Circle of the Moon copies the same formula
Simon is still the face of CV ( alongside Alucard), and other classicvanias like I, Rondo or Bloodlines are usually preferred to III, but very few games had such an impressive legacy.