NECK GUARDS FOR batters - an added protective element attached to the back of the helmet - has been made mandatory by Cricket Australia.
From now on, Australian batters must wear the neck protector while facing fast or medium fast bowlers. It's not compulsory to wear while facing spinners. Basically, the neck guard from now will be a permanent fixture with every helment worn by Australian batsmen.
While many Australian players do not prefer wearing it, including David Warner and Steve Smith, the CA decided that safety from concussions took a precedence over players' personal preferences.
The BCCI have also been aware of the concussion risks faced by batters who play with their neck exposed. A few years ago Indian players were given safety briefings on this issue, and on the usage of neck guards. However, a BCCI official had told PTI at the time that the Board could not make it mandatory to wear.
Now that Australia have made it compulsory and the tech behind neck guards has also progressed a lot, making it less cumbersome to wear, it remains to be seen if BCCI change their stance on this safety issue.