According to the link you provided, the bass bars were replaced with bigger bass bars to handle the tension of modern strings. So, it wasn't as if they didn't have bass bars to begin with (which is sort of implied by your wording).

For what it's worth, replacing the bass bar or braces periodically could be considered part of the expected maintenance of some arch-top instruments. When or how often it's needed is debatable, but instrument tops will sag over time due to pressure.