That's a strange argument; it's not about banning or not banning, it's about a) ensuring that some players don't have an unfair advantage over others, and b) that the sport doesn't simply become a technological arms race. That doesn't mean that you stop all development, otherwise tennis players would still play with wooden raquets, for example, and we wouldn't have innovations like hawkeye and TV referees. But you place restrictions on equipment so that new technology is allowed when it's readily available to all players, and when it genuinely adds something to the sport, making it a better spectacle or whatever.
This curling issue is a perfect example; it would be impossible to have a fair competition with these directional fabric brooms right now, because even if all players got them, the ones that haven't been using them to date won't have so much time to figure out how to best use them. So they're banned for now. In the future, the curling governing bodies may look at them again, and decide that they make the sport a better spectacle, and as long as they're going to be readily available to all players they might then choose to allow them.