The manufacturer has made a vehicle with a known flaw? What is the flaw? Belts are wear and tear items. That’s like saying knowing that brake pads wear is producing a vehicle with a known flaw. Many engines were designed with timing belts and no one has ever hidden the fact that it is a belt and has to be serviced at specified intervals.
Now, on the general point. I am with you. I’d rather never own anything with a timing belt (though it can be hard to avoid if you want smaller, 4cyl cars) - but they are a design decision not a flaw.