You're not buying the game because you're not happy with the product. Saying you're boycotting it is a bit melodramatic and grammatically incorrect. You boycott businesses, not their products, and it's a form of protest that's associated with some decision the business has made
outside of reasons to buy the product itself.
For example, you can boycott the supermarket Market Basket because you like the CEO (
hear about that?). You
don't boycott Chicken McNuggets from McDonalds because they changed the recipe and you don't like it.
Not buying the game because they removed the dub falls under: "Just not buying it because they changed it and you don't like the new product."
Even if you are not buying the game, not because the change is unacceptable, but because you want to make some statement about how you feel about the principle of the matter, you should be boycotting Arc Sys as a whole, not the specific game. Usually, you should probably have some sort of activism angle; trying to convince other people to boycott Arc Sys and general protesting of some form, presumably internet based.
It's fine to be unhappy about the game and not buy it; that's what I'm doing. But, use your words correctly. Boycotts mean something specific.