Why FFX? What was so good about FFX? :<
Think about it a bit. They're not making a remake. They're making a HD port. Final Fantasy X is a title on the PS2, which means they just need to clean it up a bit texture-wise, upscale it and that's it. Also, it's a fixed camera game. Meaning, they got their work cut out with alot of pre-rendered pics they can just alter the resolution of. Way easier than XI or XII, which are bigger in size and have rotating camera, as well as a bigger amount of content.
It's money in the bank. It is NOT a remake. They are NOT going to remake some other game you love in 3D. This is just the easiest game they've got to transition, as well as a very popular one at the time.
Long story short: Square-Enix wants money. This port is easy money. Money is good. Port is made.