Only Rangers, Fighters, and Paladins have access to Fighting Styles. Though the Fighter has access to all Fighting Styles, whereas Paladins and Rangers have access to a only a subset. Fighter also have access to more feats than other classes, though the Rogue gets one extra feat. Not to mention, only Fighters have access to Extra Attack(2) and Extra Attack(3). Of course, hitting with a weapon is determined, fundamentally, by proficiency and one's stat modifier with said weapon, yes. Though I couldn't imagine that the casters would be able to focus Strength or Dexterity like the fighting classes can, they have other attributes to worry about.
Tasha's Cauldron of Everything, one of the expansion books, did allow one to trade a feat for a Fighting Style though. We've no confirmation that anything from the expansion books will be added to the game, of course.
