RPG's are role-playing games. In order to play a role, you need to have choice and consequence. The player makes choices in his character's name, and they have consequences on the game world; the characters, the story, and everything else. There is no role-playing involved in a Final Fantasy game - the entire story is railroaded. Just because it's got stats doesn't mean it's an RPG.
Ironically, I totally agree with your opinion on this. I mean, just look at the Diablo or Souls series. Everyone seems to love to call them "RPGs", and I laugh every fucking time someone truly believes that they are.
Sadly, most video game developers don't care about your opinion. Even if a game doesn't have 50 different possible endings, doesn't have true "class customization" or the ability to wildly veer off and do whatever (lol "sandbox" and "openworld") you want, whenever you want, as far as video games go, it doesn't matter.
Someone decided in the mid 80s what it took for computer and console games to be considered role-playing games, and even if you don't agree, it's still used as an easily identifiable marker as to what you are possibly getting yourself into. It was probably a lot easier to just call many games RPGs instead of "linear, story based, stats driven, loot driven, dungeon driven, party driven, adventure game".
Like it or not, most, but not all of the games listed as "RPG" have more similarities with PnP RPGs than they do first person shooters, sidescrollers/platformers and fighting games.
And by your logic, the only "real" RPGs would be PnP based, or possibly MUD based. Which technically, it's true, but it makes genre classifications a lot more messy.
Conversely, practically every single game where you control a character that is not you personally, would be considered an RPG too. Look at actors. You can't say that they aren't role-playing, and they are almost always reading from a predefined script.
