Many Japanese manufacturers outsourced their manufacturing to Taiwan and still do. Then as now, a brand name doesn't necessarily imply any country of origin.
As for quality, I've found Taiwanese machines spotty: some are good, some aren't. My Janome 6500P was made there and is excellent. I have a Dressmaker from Taiwan and it's a piece of crap, whereas I've read that similar Japanese Dressmaker models (same exterior design) are good. Quality control, I suppose.