Translate another game instead of one game no one even play anymore.
Well, it's HIS time and HIS work.
If he want to spend time reworking on something he doesn't feel like it's well made - then it's his own sens of pride / ethic at work, and it's something that varies for each person and that I personally can relate to and understand.
Plus, how do you know no one play this game anymore ? I personally still have some game dating from more than 6 years on my pc that I still get back to from time to time because I like them.
You have the right to dislike this game.
You have the right to think it's a waste of time to redo a finished translation for improvement.
And yes, you have the right to say it...
But the way you say it is so direct and blunt it's border line (and some will think it's on the wrong side of the border) to a direct attack - which we ain't supposed to do.
PS : if you want that much another game translated, you're free to grab a game, some translating tool, Japanese dictionaries and get to work ^^