From the sound of things each entry is the length of a typical full size game. And this is a full remake with a lot more content. According to How Long to Beat.com, the original took around 37 hours for the story, 55 with side content. The Remake takes around 33 hours for the story and 43 with side content. That is a full size game. If each entry is of the same size, it will essentially be almost 3 times as much content as the original. I am assuming it will span 3 games. I don't see a problem with them charging full price for what is a full size game with new content.
It is kind of like saying you won't buy Mass Effect until you can grab 2/3 for the price of one game. Or any other multipart series.
Let’s just say it’s a bit more complicated than that. There’s definitely a reason (beyond pure greed) that they’ve split the games up and it kind of becomes clear as you play part 1. Remake is uhh…Not quite the right term for this game.