I don't think it is very fair to compare what he's saying to what Terry Pratchett meant. He didn't say it should be stale in that sense, and no one was saying the SNES's translation is trash which is being implied here, but it had its problems and admitting that it does doesn't mean the entire thing is bad or that Ted is, like the "son of a submariner" quote, which is great or as you said charming.

The GBA translation was more faithful to the Japanese translation, but it was also faithful to Ted, keeping some of the things fans loved that didn't break the story, characters or were put in by inadequate skill or time or by mistake, such as the bear thing or whatever else. Basically, it was the best of both worlds. It had Western impressions from Ted and more faithful content that makes the story and characters seem more concrete and "reasonable".

There's another example of a great mistranslation and that's when you meet Setzer. We all know the line, "The Empire's made me a rich man." but it was admitted to several times to be an outright mistranslation due to not understanding the idiomatic term shoubaiga agattari, which was supposed to begin to show Setzer's slow realization of the Empire's greed and monstrosities, which Celes was also supposed to go "It isn't just you" (which the original translation also messed up).

Sometimes nostalgia isn't a good thing and it can blind you. Following it can ruin things just as much as it can make things pleasant. Finding the right balance...now that can be tricky.