Seriously, what does wearing helmets have to do with batting? It's now considered part of the gear, like shoe or a glove. Viv or Gavaskar wore no helmets because they were not used to it, so wearing or not wearing helmets does not make a player great or weak.
For example, I am involved in Sofball in the US, about 6 years ago face mask started making appearance and kids, especially Pitchers, first and third base were encouraged to wear them. The Kids who started playing the game without the mask did not like to wear them because they were not used to it. But the younger age group kids who started playing the game with masks used them with no problem.
Old time coaches started saying that D1 colleges will not recruit a pitcher who is wearing masks because it showed signs of fear. In the end it did not make a lick of difference, there are some great pitchers who are going to P5, D1 colleges who are wearing masks and there are sucky pitchers who don't wear masks.